The $5000 Compression Challenge
A trick similar to the recursive Barf compressor (add information to the filename). <a href="http://mattmahoney.net/dc/barf.html" rel="nofollow">http://mattmahoney.net/dc/barf.html</a><p>A longer running challenge is <a href="http://www.drdobbs.com/architecture-and-design/the-enduring-challenge-of-compressing-ra/240049914" rel="nofollow">http://www.drdobbs.com/architecture-and-design/the-enduring-...</a> No entry fee, $100 prize, and just as unfair.<p>A completely serious compression challenge with serious consequences for AI and NLP: <a href="http://prize.hutter1.net/" rel="nofollow">http://prize.hutter1.net/</a> up to 50.000$ prize money, but severe restrictions on memory and running time.<p>You can not beat Goldman's troll-ish challenge (certainly if the rules are retro-actively clarified in favor of the organizer). You could however try to put the challenge in limbo by creating a decompressor which bruteforces a solution, 'till some hashes match or the final heat death of the universe or the halting problem is solved, whichever comes first. Goldman will not be able to ever verify your solution, and when he does (theoretically it is not impossible), it means you win.<p>Or, instead of above Schrödinger's Compressor you can send a good random number generator back as your solution. If Goldman wants his file to be random, any random file should do. Why does he want exactly his own random file? Why does he want to do a diff between two random files, is he perhaps looking for order where there is none? But that's the same foolishness he accuses his participants of.