Balance Board

 This, my friends, is a balance board. It's kind of addicting once you get the hang of it, and is really quite easy to make if you don't care about aesthetics.

 Essientially, you get a board, paint it, and put it on top of a tube. However, tubes are harder to come by than you might think- I actually had to buy one. One foot of 4" PVC pipe was about $4. the board was just sitting in my garage, so no cost there, same with paint.

The trick, then, is the final ingredient: Grip Tape. This stuff is generally used by skateboarders, and so can be found at any skate shop. However, I got mine at Dick's Sporting Goods. They sell the stuff in sheets (looks like it's meant to cover one whole skateboard, but I cut it in strips).
Normally, one sheet costs around $6, but I got it on sale for 93 cents. Great deal, right?
Update: It would appear that the reason I got it so cheap is because they discontinued the product (at least at my local Dick's)

Now, you might ask why you need it. The answer is, you don't. Need it, I mean. However, you definitely want it. Grip tape will help your shoes not slide around on the board, which can be a big safety hazard, and you also want it around the pipe/tube to make sure the board doesn't slide on that. Trust me, I tested this extensively, and you really want it.

And this is my little brother enjoying himself on the board. He kept trying tricks with it.. just make sure whoever you give this to knows that if you stand on it in the same direction as the pipe, not perpendicular, the board will shoot across the room and hurt something or someone. (he is in the proper position right now. If he were to turn 90 degrees, that's the wrong way).