DV Hardware has published a review of the Logitech Comfort Lapdesk.

If you've ever used a notebook on your lap while sitting on the couch or in bed, you probably know this can be a rather unpleasant experience because notebooks generate quite a lot of heat. I frequently work on my laptop while sitting on the couch and if I don't use a surface under my notebook my legs become uncomfortably hot after about 30-45 minutes. Besides excessive heat, many laptop users also experience other problems such as neck pain. This is were a product like the Comfort Lapdesk from Logitech comes in handy.

Logitech Comfort Lapdesk review