I second the track ball type. It's a stationary unit with a large ball about the size of a softball; this "softball" sits in a cradle so that the kids can rest their entire hand on it and as they move the ball, the icon moves. Two large buttons surround the ball that allow them to click on objects. The sensitivity isn't the greatest, but it's very stabile and allows them to improve their coordination; they can even sit the thing in their lap and work it from there. We picked ours up at ToysR-Us, but I've also seen 'em in Kmart, Best Buy and even the little 'puter store around the corner. Price ran about $29, but it's lasted 3 kids now and still works well. If you can't find a link, let me know and I'll dig the box out and give you a name.