Today I had a dead MBA when I opened the lid after leaving it closed a couple of hours. I had about two hours left in memory when I closed it. I plugged it into the power cord before I opened the lid. It took a while for the reboot button to respond. Earlier this week, I got a "you need to restart your computer" message one day. I had nothing plugged in that day or today, other than the power cord today, and I have not installed any new software. I have Mac OS 10.6.6. Before this week, I haven't had any problems. I bought my MBA 4GB in November 2010. I ran disk utility and verified the disk--no repairs, but lots of permissions repairs. Could that be why it crashed. The error code, by the way, today was Error code: 0x00000003. Anything else I should do?