The Mouse Jiggler has to be one of the strangest USB devices with a real purpose (as opposed to the Sushi USB Drives. It does exactly what the name states - when plugged in it jiggles your mouse around.
Why? Either to make sure your screen saver doesn't come on, or as a practical joke (depending on which mode you select). It was originally marketed towards security professionals and forensics experts who needed to ensure a laptop wouldn't go into a password-protected screen saver mode while they were away.
Link via BoredStop
my co-worker made it and used it while i was working,
it actually makes circles...
http://zedomax.com/blog/2007/04/20/garretts-usb-mouse-prank-device/
Many work sites, including mine, will lock out the computer after 15 minutes of inactivity (as a security precaution). And the users have no administrative privilege to disable this.
Which is no problem,,, just type in your password again.
However, if I bring my laptop home, and wanna watch a movie on it, I have to move the mouse every couple of minutes to it doesn't go into sleep mode. It's annoying.