For a long time I didn’t use a lapdesk, since hey, why not just use a pillow? But after owning a simple and cheap lapdesk for a while, I can say that at the least, the one I own is great. I use mine on the couch, in the bedroom, and oddly enough use it for food too, so it’s not just for laptops.
I looked at a few lapdesks, and the one below is my favorite, in part because it is simple: thin, cheap, the side part retracts easily and is secure, and it also stores easily since it is thin.
Logitech N315 portable lapdesk and cooling pad
The one above is in silver/white, but I own the one below:
The plain black and grey version works great. The grippy-ness holds my laptop well, and keeps me shielded from the extra heat, without having a noisy fan, not bad, not bad at all.
Here are the many other styles of the Logitech N315 lapdesks as well, if the basic black or white are not your favorite.