Similar experience here. My Compaq Presario R4000 laptop stopped working abruptly while I was sitting in the university lab. It wasn't even plugged in, was running off the battery, and the display just went blank. The LCD had probably conked off, for I could run an external DFP off it. Anyway, since it was still under warranty, I shipped it off. I got a call from the service center, saying that I had dropped liquid on it, and the hard drive, motherboard, CPU and LCD were all shot and had to be replaced, and gave me a bill of around $700 (original cost of the laptop was $1200). I was livid, but no amount of reasoning/cussing changed anything. "We'll ship it back if you don't want to fix it". Fucking turds, those Compaq folks. Will never buy anything from them every again, and anyone who's heard this story has refused to touch HP/Compaq again.
Oh and the best part? I had purchased a $99 user-damage covering on-year warranty from them when I bought the laptop. So they had to replace everything or me, essentially handing me a new laptop. I got lucky.