My MacBook has died on me (update: and now it’s fixed. Logic board problem, got it back from the Apple Store in London on the 14th) I opened it up when I came downstairs on Saturday morning and it was frozen, trapped in stasis instead of downloading emails or telling me what my FaceBook friends were up to.
I rebooted, restarted email, and it froze again.
I rebooted. It froze, this time during startup.