I'm going on a very boring, 3 hour trip. My laptop battery will last me long enough that I can have a computer during that time, but I thought I'd ask first, is this a bad idea? Could bumpiness during driving crash the harddrive, or cause other damage to the laptop while it's turned on?

It's a Sony VAIO VGN-A690, and it's pretty heavy. I'll have a hard surface between it and my lap to keep it from overheating. The car will be a van, and it will be fairly clostrophobic in the back, so it shouldn't end up moving around. Can it handle it?

Well, a laptop can handle minor to fair amounts of jolts. But in the end, it is a hard drive and the normal rules apply. Don't let it fall off, don't use the machine on bumpy terrain. It'll be fine while driving under normal conditions.

Laptop harddrives can handle quite a lot. I used to ride my bike with a running laptop inside it. I think I was the first person with a 4GB portable MP3 player. Oh... The laptop kept running for years after using it in this way.

Well, the trip was canceled, but it's good to know this. Thanks a lot guys.