What do you get for claiming a bounty? Typically a "bounty" implies money, but I can't find actual currency amounts anywhere.
Maybe the bounties are all already-claimed and either the amounts were never disclosed or the site didn't think the amounts were relevant.
Also, I wonder if they'd accept entries for software platforms. Like, for instance, the 9Front oparating system ships with Doom pre-installed. But maybe also things like "has Doom been cross-compiled into Brainfuck?" or the whole Doom-in-Redstone thing.