Mouse Jiggler Code for the inexpensive DigiStump Arduino Compatible USB Dongle
You can find these modules for less than 2 bucks as clones: https://www.ebay.com/sch/i.html?_nkw=digispark
You can find the real deal at: http://digistump.com/products/1
Uses the mouse library from https://github.com/digistump/DigistumpArduino
Follow instructions from this post to avoid the 5 second delay before the devices acts as a mouse. http://digistump.com/board/index.php/topic,1868.msg8432.html#msg8432 This link might be useful too? https://digistump.com/board/index.php?topic=1837.0