KeyboardLock (PPC) 1.5 Description:
KeyboardLock lets you reclaim desktop space any time you need it by locking your keyboard. Once locked, you can safely place things on it, and still use your Mac for anything that doesn't involve typing. The keyboard is toggled simply by moving the mouse to one corner of the screen, so it's a snap to use. Or you can use AppleScript to password protect your keyboard.