Ooh! I hadn't thought of RDC. If you have a home network and that old PC is running Win2K Pro or XP Pro, Microsoft makes a free client you can use to control it from the Mac, an other options for occasional Windows needs. I won't belabor that at the moment, but I can tell you more.
(Actually, Macs are designed for hard surfaces, anyway, and are more correctly referred to as notebooks than laptops.)
Your lap is a pretty ergonomically crappy plave to use any notebook computer. The only reason they were named that is because when computers first started hetting smaller, they were referred to as desktop computers -- the next step was laptop, and now some folks who can't let it go call PDAs hiptop or palmtop computers.
If anyone uses a laptop routinely, anyplace but on a hard surface, they're asking for problems (heat and airflow).
I don't know how many I've seen burned up because someone puts them in their laps, then decide they need a nice thick quilt over their lap, to keep their legs from getting burned.
If someone must use them as laptops, instead of notebooks, a notebook cooler is a "must have" accessory, but buy the thick ones, with side vents.