I had 'hotlap' as well. I also suffered a deep vein thrombosis in my leg, so HAD to keep stuff off it. I came across (on freecycle) a nifty little thingummy - a table for people who are bedbound. The wheels on the base slide under my chair, the support pole comes up the side, then the table adjusts to be just over my lap. It also means I have somewhere to park my mouse, tv remote and a cuppa - I use the optical mouse on my jeans leg. When I need to get up out of my chair, I dont have to struggle to find somewhere safe to put the laptop.