Balance board + Wii Motion Plus = Hoverboard jousting.
Balance board + Wii Wheel + Wii Zapper = Gas and brakes and steering, co-op racer, 2nd player shoots in 3-D on-rails-style drive-by.
Dual Wii remotes = One hand is a pistol, one hand is a flashlight, you're lost in the woods at night, and there are werewolves out there. Adds more spookiness than having a fully automatic assault rifle with a flashlight already on it, like most other shooters.
Dual Wii remotes = rocketbelt from Pilotwings 64, OR Pod Racing style rocket racing game. Each hand controls a jet.
I haven't finished this idea yet, but something involving shooting different types of food, like burritos and pizza, into outer space, possibly to shoot down spaceships. I'm not sure if the character needs a good motive or not. But this game revolves around the physics of burritos exploding when they hit things in outer space, and then beans floating around without gravity. Maybe aliens are invading and their only weakness is food, and you work at a restaurant with a food cannon?
I'd be fine with 1% or so of the profits after all the costs are accounted for.












