Windows only: Free application CircleDock automatically puts files, folders, and shortcuts within a few pixels of your mouse when you invoke it for quick action. CircleDock is completely customizable, from the skin and hotkey to the items you place in the dock. You can rotate the items in the circular dock with your scrollwheel, which is cool despite its questionable usefulness. The app is portable, so you can toss it on your thumb drive and take it with you. CircleDock is free and open source, requires .NET 3.5. A more attractive and improved update is expected within the month. If you give it a try, let's hear what you think in the comments.