Seems like the usual obfuscation and/or VM approach. I don't think it's all that revolutionary as they make it sound, but it could be a good implementation.
The current incarnation of the contest is supposed to only run on a couple of models of Dell WinCE devices. Before I can get interested, they will have to give me a Windows version of the challenge code to play with.
Plus, it looks like they tie to a particular model and speed of CPU, which is going to limit practicle usefulness, I think.
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