Any particular genre? Remakes?
Racing:
I think an RC car game (sorta like RC Pro-AM) would be cool. Except it would be more interesting on dirt tracks. Although now-a-days those miniture RC cars are more popular.
or
The game that was like sprint, with the 4 colored cars, except it was Trucks on a dirt track. I'll have to try to remember the name. The track was basically psuedo 3D. I remember that it was always alot of fun to play
Simple Arcade:
Scorched Earth is always a good remake to get involved in. It has weapons, upgrades, explosions, projectiles, simple physics, AI that isn't too far fetched... And I have always been fond of the game.
Keystone Kapers, Kaboom!, Barn Stormer etc...
More complex Arcade:
A Space Harrier remake, (pseudo 3d).
Spy Vs. Spy
Turn Based Strategy:
A game like Advance Wars, but with a differnt theme. Middle Ages, Space age, Fantasy (wizards, magic) etc...
Puzzle Game:
Klax
Sorry if these ideas suck. Are you looking for a completely original idea? Well, perhaps I will have better ideas later if none of the above interest you.
~zen