I set up iTunes to organized all my music in folders by the artist name.
I have all my pictures that Ive ever taken organized by the year, month, and date taken (20111204), all the way back to 2008 when I bought my first camera.
All my school work is organized by school year, and class.
It rare if I cant find something on my computer. or the internet for that matter.
And I have set up email filters to organize any Facebook, Twitter, robotics, Amazon, Netflix emails into their corresponding folders.