When I am tired, I fiddle with my background image and cursors. I adjust the sounds my computer makes for its default beep. I repeatedly check e-mail, or see if there are new versions of utilities available for download.
I found it useful today to just spend the last hour of my time at work reading a new book on object-oriented programming. I will be posting a more thorough later. The book is by David West and titled Object Thinking. I'm about halfway through it and am thoroughly enjoying it.
Rather than complain about lack of sleep, I best head off to the land of Nod. God bless you all.