Jason at Signal vs. Noise has a Productivity Tip: Throw everything on your desk in a box
Toss everything, and I mean everything on your desk in a box. If it doesn’t fit in a box, put it on the floor. Your desk should be completely cleared of everything — no monitor, keyboard, mouse, pencil, paper, stickies, gum, etc.
Next, get to work. Only remove something from the box (or the floor) when you absolutely need it. Not before. No anticipation. If you don’t need a pen now, don’t get the pen. Only place it on your desk when you need it.
Throw out the remaining items in the box in 30 days or sell the contents on Craigslist. Disclaimer: Before you toss it, you may want to go through it and make sure you pull out the picture of the family and the legal documents, but toss everything else.
Just did this, and I already feel "cleaner." Lots of entertaining comments on the original post as well.