This past weekend the first submission for the Cartridge Classic II came in: D4RK3 54B3R submitted the first of two planned entries.
For those who are on the fence, remember you can do both this competition and the casual competition that's going on right now. The deadline for the Classic is December 1, whereas the deadline for the casual contest is September 19, better known as Talk Like A Pirate Day. That means you still have time to put together a game for the casual competition, and then compress it down (stripping features if necessary) to submit to the Cartridge Classic later on.
If you're wondering what kind of game you could realistically do in 8K, I'd have to say the field is wide open. I probably could've squeezed a ton more features in Runt, a 4K game, if I merely had 1K more to work with, and that's not even counting the benefit of libraries. (I recently saved enough bytes from further compression that I'm hoping to do a Runt relaunch with more maps and more variety.)
8K is more than enough to do many board games, as Ben G demonstrated the last time. A strategy game should be plenty doable. Action is easiest of all, and puzzle-action would work too. 8K is also enough, I think, for a good dungeon crawl or an open-ended RPG that can generate maps or quests from a file.
What kind of games motivate you? Do you want to make something with a fall or winter theme? Would you like to make a game that one person can play alone, or a great game for multiple players, or something that can work for both? There's a lot you can do in 8K, especially with isometric graphics, skins, and big icons on the table.