In addition to the normal keyboard, mouse, monitor etc.. I have
Logitech WingMan Force Feedback Joystick (dont use much)
Aiptek PenCam Mega usb-camera (dont use much, either)
Headset
Labtec speakers (with subwoofer)
Western Digital My Book Premium ES Edition
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it's an eSATA drive that I use as a normal hdd, it's always on, and works as fast as a normal hdd, but it is outside the pc tower and makes less noise..
Zoom GFX-4, (electric) guitar effects processor