Download the Collin the sheep screensaver - made by Matthew Thomas himself!
Instructions:
Unzip the folder and put both of the files into the place where your screensavers are stored. This is usually in Windows or Windows/system32. It depends on what version of windows you are running - XP stores screensavers in windows/system32. A good way of finding out is by searching for 'SCRNSAVE'. It'll tell you where that file is and that's where you want to put the files. If you are having problems, Email me and I'll do my best to help.