For some reason, my single core processor is now constantly running at 100%. As you can see in the screenshot of htop, the process /usr/bin/lxsession -s Lubuntu -e LXDE is taking up most of the processor's power. Obviously, I can't kill it, but what else should I be looking for?
I'm running Lubuntu 12.10 32-bit on an old laptop. OS normally use approx 2% CPU at idle.