Bungie's filed a new trademark to secure the name Marathon for a videogame.
Marathon, remember, was Bungie's game for Mac from a million years ago. There's no other evidence of a remake, but the name alone should start people talking.
Marathon: Durandal - a bit like Doom but with colour - was ported to Xbox Live Arcade in August 2007. It wasn't as good as Halo.
Bungie is currently hard at work on new game Halo: Reach, which will be released this autumn.