Incidentally, I had to explain to my wife why I had to jump on the computer immediately when getting home from work and I never thought I would see the day when I would be chastised by my wife over a GPL violation. :)
The DOSBox folks and the Google engineers working on Native Client are geniuses. By comparison, my C++ skills are only slightly more sophisticated than the monkeys you see throwing poo at the zoo. :)
Take a look at what I hacked together. I had a lot of fun working on it over the last couple of weeks.
Yeah, I don't think the old loophole of running GPL'ed code on your server would apply here since DOSBox would be downloaded and executed in the browser. He has to release the source.
Furthermore, he didn't just adapt the build scripts. The game files are not mounted from a discreet disk image, he made a hack to get them available from the DOSBox internal Z: drive (which isn't actually a disk image but the interface to internal functions).
Oh, one more thing. My goal with the site is to share the port and be able to pay the bandwidth bills hosting the demos. It's definitely not my day job. :)
Publishing the source wouldn't have hurt his income and would have prevented some bad advertising.