Ok, here's some free ideas I thought of today.
1. Shaving lotion that turns hair bright green, so as you shave, you can see where you need to shave more. (I'm sure people with dark hair are saying "Dude, why don't you just look at your face?" Lot harder to see with a blond beard.)
2. Tray-tables for people in the backseats of cars.
3. When you buy a hybrid, you can program it to know what car you traded-in. Then as you go, it can show you how much you've saved by buying the hybrid.