We all know that Santa is a Christmas icon but these Santa Claus icons take things quite literally by making him one for your Mac.
Santa Claus Icons is a collection of five Santa faces that express feelings of anger, happiness, frightened, tired and sleepy. There's surely room for a few more emotions but the creator of the set has decided to stop things there. The icons are in PNG format, free to use and all very well illustrated.
To replace a standard icon with one of these, open the Information dialog and copy the image to the clipboard. In Finder, select the icon to be changed, click Information and inserts the new Icon. Alternately, you can use an application like CandyBar.
If you want to get closer to Santa without going into his grotto, Santa Claus Icons are a nice collection.