The Mouse Jiggler stops your computer going to sleep or the screensaver triggering. Offered in a fast or slow version for $29.95. Words fail. Via

Computer Forensics Investigators use Mouse Jiggler to prevent password dialog boxes due to screen savers or sleep mode. IT Professionals use Mouse Jiggler to prevent password dialog boxes due to screen savers or sleep mode after an employee is terminated and they need to maintain access to a computer. IT professionals or office workers use Mouse Jiggler when downloading/installing programs to keep overactive screen savers from interfering. Not many can resist watching the reaction of a coworker encountering the fast Mouse Jiggler for the first time.