This is my first instructable so constructive comments are appreciated. I originally posted this on my blog, and after much grudging by my friends to post here, I decided I should. So here goes.
This thing turned out to be surprisingly versatile, and much better to use in practice than I had originally anticipated. The one pictured here gives me about 120 degrees of movement around the two horizontal axes and 360 around the vertical. Not too shabby.
Step 1: Materials
. one tennis ball.
. 1/4' bolt (that fits your camera, be careful to get the right tread. what's it called?)
. a nut, butterfly nut and a washer.
. a tube or can that the tennisball will snugly fit into. Doesn't matter what kind, it should be sturdy. Try using the can that the balls come in.
. some tape and a knife or something.