i used them as frisbies and that quickly evolved into target practice. i saved the jewel cases and used them for my mix cd's. put one unopened disc in a time capsule, saved 1 of every version unopened as a collectors item in a box and threw the box in a closet(you never know 20+ years down the line)
made a toy periscope with some and a carpet tube for 2 of my cousins, made a prism baby crib mobile for a friends 1st born, went around the twin cities to about 10 best buys and various other stores like office max, office depot, compusa, computer city, circuit city and took all their free discs and made a nerds home gym for the guys in my IT class after i ran circles around them while mowing them down in the tiny basement of splatball inc. to which they subsquently replaced the wheels on my truck with them the following day and having to rollerblade 15 miles home because they hid the wheels in the mississippi river on campus. that was the last time i parked on the downhill side of campus.