No less than once a week I hear about random corporation violating the license on some piece of open source software. The Free Software Foundation says that this happens all the time, but once the infringers are informed about their violation they typically correct the problem very quickly. Such failures typically include: not including a copy of the GPL or whatever license the software has been released under; not providing source code or an offer to supply source code; blatantly using GPL code and then licensing the complete work under a restrictive license.
Instead of notifying these companies and asking them kindly to comply, and then letting them off scot free, why don't the developers freakin' sue already? Sure, it costs money, but the great thing about lawyers is that they tend to overlook your lack of funds if they can see dollar signs on the horizon. They do it for insurance, liability and accident claims, I'm sure there's some ambulance chasers looking to make big bucks in copyright law too. The whole "sue for revenue" model isn't likely to go away. Large companies are just too pitiful at due diligence to actually follow a license as complicated as the GPL.
So what do you need to pull off this get-rich-quick-scheme? Well, number one is you need some copyrights. Thankfully, that's really easy to get, just hire some student programmers to work on open source and put your company name on the contribution. Once you've got a stake, no matter how small, it's my understanding that you can sue any infringers just as well as the major contributors. Of course, this tendancy by open source projects that are run by corporations to get copyright assignment on all contributions will trip you up.. guess you'll have to avoid those projects. Next, you'll need lawyers. Scum sucking, bottom feeding ones. You'll need them to review violations that you pay people to find in some "work from home" scheme. You'll also need them to send nasty letters and pull dirty tricks so the company can't weasle out of paying by complying with the license after the fact.
Speaking of paying, how much can you expect to get out of these fat corporate giants? Well, if you were to go to court you could expect to get at least "statutory damages" which is a minimum of $200/copy. But that's chump change. Typically any profits the company made that can be attributed to the violation will be awarded to the copyright holder, and that almost always exceeds the statutory damages by an order of magnitude. Then there's the punitive damages, which apparently don't exist in copyright law but always seem to be claimed, which tend to be around $70,000/copy.
So really, suing people who didn't bother to read the license on your open source software and have made a mint by unlawfully distributing your code is so easy even the most Lionel Hutz of lawyers should be able to get you a big fat payout. Then you can hire more developers, more people to look for copyright violations, and more lawyers in an endless regression.