When I was a kid I LOVED taking stuff apart. Mostly radios and watches. I loved the wiring, the gears. Because I had no clue as to how to reassemble the objects, I saved the parts and made other stuff out of them. Mostly pop art. I wish this Gear Clock ($15) from Think Geek had been around at the time. Not only can kidlets take it apart but, because it's color coded, they can put it back together again too!!! The small parts make it not appropriate for children 3 years or younger, but that doesn't mean you can't buy one NOW and play with it until the wee one is ready for it!!