Windows only: Hot Corners, a free utility for Windows desktops, adds the "hot corners" abilities of OS X's Expose system to any Windows desktop. The system tray utility can assign actions like minimizing all windows, locking a system, showing the My Documents folder, and others to any corner of the screen you run your cursor into. There's also a "Mouse Move" feature for those who'd like fewer accidental actions which requires holding the Windows and X keys while dragging the cursor before acting. While it lacks the full-fledged Mac-cloning features of DExposE2, it's pretty handy for being so small. Hot Corners is a free download for Windows systems only.