Hey you! Fight the generic Microsoft green-field background and get something not only cool, but sciency and astronomy-ey! Phil Plait of the Bad Astronomy blog constantly posts LARGE images taken from Hubble, NASA and other astrophotographers and shares them with his readers. A lot of the images are HUGE! Because of that, they make fantastic desktop images!
Or use mine! And perhaps someone can tell me whether or not this actually IS the most updated map of our fair Galaxy (there’s quite a few maps out there.
Update: That third “HERE”, Credit goes HERE!