In the IPO world, it seems to be the year of private equity. Many of the top-performing companies that hit the market have been “boomerangs,” meaning they were part of going-private transactions previously.

Just take a look at this sample:

Of course, the trend should be no surprise. From 2000 to 2007, there was a huge burst of going-private transactions, led by firms like KKR (KKR), Blackstone Group (BX), Apollo Global Management (APO) and Carlyle Group (CG).

But for those firms to actually make money, they need to either take their portfolio companies public or sell them. This has another interesting name: harvesting.

With the equities markets in bull mode, the preferred option has been IPOs. After all, the average return of an IPO for 2013 is 20%, while the gain has been a sizzling 29% for those companies with market caps over $1 billion.

The wave has been about more than just a strong market, though. For the most part, private equity firms have become more operational with their portfolio companies. In fact, they didn’t really have a choice. With the financial crisis in 2008, there was an urgent need to restructure many companies, which often meant greatly reducing the cost structures.

Plus, another benefit has been rock-bottom interest rates. Private equity firms have been able to refinance their existing debt, which has meant even lower costs.

Toss in the uptick in the economy — which translates to growth on the top-line as well — and it should be no surprise that private equity-backed deals are hot.

Still, investors should be a bit wary. When top dealmakers are eager to unload assets, some skepticism is warranted. For example, Apollo’s CEO Leon Black recently said:

“We think it’s a fabulous environment to be selling. We’re selling everything that’s not nailed down. And if we’re not selling, we’re refinancing.”

That’s hardly something you want to hear … especially when you’re the buyer of IPOs.

Of course, Wall Street never seems to lack enthusiasm and speed for the most part. Thus, there is a healthy pipeline of major private equity deals ready to tap the markets, such as HD Supply andCDW.

But investors will reach a breaking point eventually … and maybe pretty soon. Just a few concerns include rising interest rates, volatility in the equities markets and continued weakness in Europe and even China.

The bottom line is that IPOs are a risky game, and booms generally do not last long. So if you see a private equity deal, you still need to do your homework. Things may start to get tougher quickly.

One of the nice surprises of 2013 has been the hot IPO market … and even small-cap deals have enjoyed a nice run. This has certainly gotten smaller Wall Street underwriters excited, and the president and director of equities at JMP Securities said in a recent interview that it points to rising investor confidence.

But is the big action really with small caps? Well, if you look at all the deals for 2013, those with market caps below $1 billion has an impressive average return of 18.16%. Here are the top five performers, with returns based off the offering price:

The two cloud operators  – Rally (RALY) and Tableau (DATA) — are hardly a surprise, but there was some diversity. Fairway (FWM) is an organic grocer, Artisan Partners (APAM) is a financial services company and ExOne (XONE) is top player in the hot 3D printing market.

On the flipside, though, there were some small caps that were big busts. Take a look:

Of course, that’s because small caps are often volatile. They can certainly have huge plunges even when the overall market are performing well .. and even if a company is in a hot space. After all, Marin Software is a cloud operator.

And while it’s hard to be disappointed with small caps, larger deals have done much better. So far this year, the average return has been 24.95%. In fact, Consider that there was only one deal fell below its offering price: Ply Gem (PGEM). And its return is still only a minor loss of 0.33%.

Here are the top five offerings:

In other words, investors who have focused on on IPOs with market caps over $1 billion have done the best. Heck, it’s been nearly a can’t-lose proposition.

Even if investors seem to be warming up to small caps, they are still looking for established companies that can produce decent growth rates — and are not afraid to bid them up aggressively.

Cloud provider Textura (TXTR) pulled off a successful IPO today, with the shares spiking 56% to $23.39.

Like many startups, the early days were fairly modest for the company (the launch was back in 2004).  The original office was only 800 square feet!

The co-founders of the company — William Eichhorn, Howard Niden and Patrick Allin — were former PWC consultants and they believed that the commercial construction industry was ripe for innovation. Keep in mind that the processes were often manual, inefficient and error prone.

But the co-founders did not rush things; instead, they spent nearly 5 months researching the industry. This involved talking to many general contractors, subcontractors, materials suppliers, architects, banks and insurance companies.

“We wanted to understand the industry and how the key processes worked,” said Patrick, who is the CEO of Textura. “After this, we realized there was a big opportunity.”

Yet the first step was to apply for a patent. “We thought we had unique innovations,” said Patrick. “There were also few patents in the construction industry. So we drafted the patent ourselves.”

It turned out to be a very good move. “The process of writing a patent creates real discipline,” said Patrick.  ”It helped us focus on building better products for our customers.”

The result has been a full-featured management system, which helps with bidding, estimating, pre-qualification, contracting, project management, invoicing and payment processing. And yes, Textura did not stop with the patents. The company now has 40 issued and 52 pending patents in its portfolio.

As should be no surprise, Textura has been growing at a rapid clip. From 2010 to 2012, revenues surged from $6 million to $21.7 million. Since inception, the platform has managed over 13,000 projects, totaling over $125 billion.

A big driver has certainly been Textura’s innovative offerings. But the company also has a powerful go-to-market strategy. Since the product relies on collaboration, there has been a network-effects to the business. Consider that a typical project has 40 participants.

Something else: Textura does not even have a traditional direct sales force. Rather, the company distributes its products through its own client services organization. “The people who sell the product are the same people who implement and support it,” said Patrick. “It’s an approach that has been popular with owners and GCs.”

Going forward, Textura’s opportunity looks bright. The global market for commercial construction is about $7 trillion per year. And so far, Textura has only scratched the surface.

According to Patrick: “The revenue opportunities are in the billions and billions.”

Tableau Software (DATA), which provides software for analyzing trends and data, might not be a household name, but it certainly caught the eyes of Wall Street on Friday.

Ahead of today’s initial public offering, Tableau boosted its transaction from a range of $23 to $26 to a range of $28 to $30, and also increased the number of shares issued from 7.2 million to 8.2 million.

Tableau ended up pricing the deal at $31 to raise $254 million, then investors bid shares up as much as 60% in the first few hours of Friday trading.

So why the excitement?

Tableau is one of the leaders in a red-hot market: Big Data. Amid the surge in mobile, social networking and the cloud, companies need better tools to make sense of the subsequent deluge of information. Tableau’s software not only makes it easier to access this data, but also to put it into understandable forms, such as graphs and charts.

Think of it as Excel on steroids.

Speaking of steroids, Tableau’s growth has been almost unnaturally robust, with revenues surging from $34.2 million in 2010 to $127.7 million in 2012. The company is even profitable, with net income coming to $1.4 million last year.

In all, Tableau currently boasts more than 10,900 customers, including top-notch organizations likeDeere (DE), Deloitte Touche Tohmatsu, Verizon (VZ) and DuPont (DD).

As a note, Tableau is just the second Big Data company to come public. The other was Splunk(SPLK), which hit the market about a year ago and has since gone on to post a gain of 163%.

Still, despite the clearly mouth-watering possibilities, investors should approach DATA stock with caution in the short-term. It’s typical for shares to cool down after such a hot opening — as was the case with Splunk, which shed about 25% within two months of its offering before finally snapping back.

Today Cyan pulled off its IPO, raising about $88 million. The company is a top player in the software-focused networking space.

No doubt, the growth ramp has been substantial. From 2010 to 2012, revenues soared from $23 million to $96 million.

I had a chance to talk to the company’s CEO, Mark Floyd. He certainly has a great background, leading companies like SafeNet and Entrisphere. He was also a venture capitalist at both Sevin Rosen Ventures and El Dorado Ventures.

Here’s what he had to say:

Q: Since the telecom implosion a decade ago, there has been little investment in the equipment space. That’s been a benefit for Cyan?

A: We do not have the legacy problems of companies like Alcatel-Lucent . This gives us a significant advantage in terms of innovation.

But it has not been easy. Cyan was started five years ago when there was no interest in funding companies like ours. But the timing turned out to be spot-on in terms of the market opportunity for the technology.

Q: A key is that the network was meant for voice not social networking, cloud apps, games and so on?

A: That’s right. The network has become too expensive to scale up by adding routers and equipment.

This is where Cyan comes in. We are focused on softwae defined networks (SDNs). This allows our system to be more flexible and open. The architecture is also much more simplified.

We think of ourselves as the VMware  of the network. VMware virtualized the data center, which resulted in huge gains. We plan to do the same with our systems and software. We look at this as a fantastic opportunity

Q: What about the business model?

A: For our Z-Series hardware, we recognize revenue when the product ships.

But then we have our Blue Planet software, which we sell on a subscription basis. This is available even if a customer does not buy our hardware.

In the coming years, we think Blue Planet can turn into a large business, with a strong base of recurring revenues.

Chances are you haven’t heard of Azul Systems … but you’ve probably benefited from the company’s back-end technology. Essentially, Azul develops systems to help improve the Java language, which is the bedrock of many important web apps like stock exchanges, auction sites and e-commerce platforms.

When it comes to today’s requirements for financial transactions, every second — or millisecond — counts. That’s the laser-focus for Azul.

Azul’s main competitor is the mighty Oracle (NASDAQ:ORCL), but its underdog status has not been much of a problem. In fact, the smaller company keeps stealing customers. One of the latest wins was the LMAX Exchange — a fast-growing forex market platform that processes about $3 billion in daily transactions and, at peak levels, can handle 40,000 transactions per second. It’s a prime example of Big Data.

Azul sure isn’t short on backing either. Since Azul was founded in 2002, it has raised over $100 million in venture capital. Some of the investors include tier-one firms like Accel Partners, Redpoint Ventures, and JVax Investment Group. It’s a good bet that Azul will eventually look for an exit, whether via an acquisition or IPO.

In fact, I recently had a chance to talk to the company’s CEO Scott Sellers, whose tech career spans more than 23 years. Back in the 1990s, he founded 3dfx Interactive, which was a developer of high-end graphics cards often used for video games. He took the company public and then eventually sold it to NVIDIA (NASDAQ:NVDA). Along the way, he was able to get eight patents issued in his name.

In our interview, Sellers talked about the current environment for tech — which he thinks remains robust — and the strong trends for enterprise technology, especially in light of the mega-trends like mobile, social networking and cloud computing. He also has some interesting things to say about the recent deal with the LMAX Exchange. Take a look!

The initial public offering of Rally Software (NYSE:RALY), which operates a cloud platform for software coding, came out sizzling today. The company not only priced 6 million shares at $14 — above its $11 to $13 range — but the stock has since surged 30%.

Rally’s platform is based on a type of software coding approach known as “agile” that focuses on speeding up development and improving quality of design.