[ubuntu] Mouse moves down to lower corners on its own

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http://ubuntuforums.org – I've seen my mouse exhibit the most strangest behavior. It seems to be drawn to move, on it's own, without any action on my part, to the lower left hand corner of my screen. At first I thought it was just happening in Firefox but today I noticed it also happens when I'm viewing the desktop. I have to play this game of tug of war with the mouse cursor to regain control of it for awhile. In addition to that if it stays there too long my whole system freezes up and the keyboard becomes unresponsive as well. What could be causing this cursed, cursor drift? The mouse is a Microsoft Comfort 3000. A (Hardware)