I really want to see a Disgaea style game where instead of just going into items to boost them, you can go into your other characters' minds to unlock greater potential or something.
I would also be amused by a system where your stats could go a LOT higher...For a while I imagined a system where the numbers in any given stat changed to a new color every 'thousands' place, and only the top three or four digits were displayed. Quite amusing if such a system was based on the ROYGBIV spectrum, and you had a chance to do 999 violet damage to a critter with, like, 10 red hit points. (squish) Numbers that cross barriers, like 12,345, would be displayed as 123 and could be written as '12.3 orange'. I guess you could get really really big ones with special glow effects and wrapping the scale around, so something like 'gold glow violet' would be...huge.
Hmm. Would '999 violet' still be as awesome as '999,000,000,000,000,000,000', even if they represented the same concept? On one hand, you're not displaying as many numbers, so it's inherantly less cool. On the other hand, "999" in purple takes less screen space, so you can HAVE more different stats. I'd say use a scale of 999, 999K, 999M, etc, but that breaks down when you get to Quadrillion, Quintillion, Sextillion, Septillion... Too many numbers with the same first two letters! Though I guess you could do K, M, B, T, Q, I, X, P, O, N, D...