Law doesn't really work for the little guy, sadly. It's next to impossible to get a lawyer to take on a case like that when you don't have a ton of money to pay them up front (like if you were bootstrapping a big open source project yourself and trying to make a commercial go of it). I know, I asked a bunch of them. There's a reason the vast majority of GPL violations go unpunished.
As a thought, since it sounds like you had fairly solid evidence of their shenanigans... maybe a blog posting on PortableApps detailing the problem + evidence might have been enough to get them to change their ways.
The PortableApps website + Community has decent reach after all. :)
Timeline-wise, was their legal dispute with Toys "R" Us over by then? If not, it may have been useful to let Toys "R" Us counsel know... ;)
At the time, I was under an NDA regarding negotiations of a possible deal with the very large memory vendor that ultimately picked Fuhu so they could have used that as a venue to sue me. Even now that the NDA has expired, I only shared a small portion of the situation. Sadly, if you can't afford to defend yourself in a lawsuit, you can't afford to speak truth to power.
The FSF only goes after folks that violate software they own the copyright on. The EFF and SFLC only help non-profits and only in very specific circumstances.
I believe the FSF only sues over code the FSF itself owns the copyright to, rather than acting as a general GPL-enforcement agency, since their lawyers feel themselves on more solid footing in that situation.
I'm sorry to hear about this. How do lawyer's think about this situation (up front vs potential earnings) for something that seems like it could be a sure thing?
Are there any legal financing options available to manage the fact that cash is needed up front?