My Dell blew up too
In February 2006, my laptop started to smoke and catch fire in my bedroom, under normal use. I contacted Dell, and they requested the laptop be sent in immediately, and a replacement would be issued.
I was told by a manager at Dell's Repair Center that the fault started on the system board, and had caused the smoke and fire. I was not released any further details, and any questions I asked were either brushed off or instructed at Dell's coprate office, in Texas.
After about 3 months, with another 1150 (The replacement), it too started the same problems I was having just before unit #1 caught fire. It was locking up constantly, and certain things on the laptop would not work. I contacted Dell that evening, and at 230am EST, the laptop began to emit smoke.