You know, when I was a kid I was very much into radio-controlled vehicles. What can be more fun than maneuvering one of those things through a home-made obstacle course? Well, this kind of fun is not just for the kiddies. RC Trucks are a hobby that grown up kids can enjoy just as much. Maybe even something they can share with the youngsters. The link above will take you to a site that can provide you with a ton of information on a variety of different remote control vehicles -- cars, trucks, boats... even planes!
Check it out and maybe you can recapture a moment of lost youth!