My wife and I have been using Tablemate II's (you can get them at Bed Bath and Beyond stores, definitely; not sure where else) for a long time now for our laptops. Their height/angle is decently adjustable and I've had pretty good luck with it with my 15" Macbook Pro. It leaves enough room for the laptop itself and a mousepad with a little bit of room for maneuvering the mouse. The best thing about them, though, is the fact that they're only about $20-25 and pretty sturdy.