If I'd known it was lights out day or whatever it was, I'd have shut everything noncritical down and gone to bed. But since I didn't, I stayed on the couch with everything running.
As more proof I wasn't feeling well, I discovered I'd not logged in to LJ for two full days. Took skip 260 to catch up.
Still feeling low on energy, but so far I haven't dozed off in the three hours I've been out of bed.