Why the %^&*# does my taskbar have a mind of it's own?

I’m talking the notification area, where the time is, down on the right (Windows Vista Ultimate 64 bit). One day it will show me icons it’s supposed to, the next day it won’t. FOR INSTANCE, since I use a wireless keyboard, there are 3 icons (num lock, caps lock and scroll lock) that are set to SHOW, and today they don’t. In fact, today they’re listed under “past items”. I know the solution is to reboot, but it’s a pain, it’s a problem and I want to fix it.