The folks at ArkaneSystems have created a wonderful life hack known as the Mouse Jiggler of which can save a lot of frustrations of having to enter your creds the moment you step away from your desk.

Feel free to get a copy of the Mouse Jiggler @ CodePlex.

Project Description

Mouse Jiggler is a very simple piece of software whose sole function is to “fake” mouse input to Windows, and jiggle the mouse pointer back and forth.

Useful for avoiding screensavers or other things triggered by idle detection that, for whatever reason, you can’t turn off any other way; or as a quick way to stop a screensaver activating during an installation or when monitoring a long operation without actually having to muck about with the screensaver settings.