Apple Thoughts: Tidy Up Your Mac

"Spring may be in the air, but if you've spent a long winter packing your Mac with applications, files, and folders, there's a good chance it could use a stern cleaning."

One of the best tips is to keep your desktop clear I think. This is especially true for "switchers," that don't realize Finder treats any fold or file on the Desktop as a window, and it will slow your Mac down if you get too many displaying. Might as well use the built-in tools OS X gives you to organize your work (Documents in your Finder window). Oh and don't forget to dump the trash, since even though files are there, they aren't truly off your system until that little trash can is empty.