And if they get too small... The distortion on the image becomes too great. Might as well just post links to the full-size image instead of posting an img tag at that point.
I've seen this done on other gaming forums, and seen some realy cool desktop backgrounds (: so basically, i'll start, all you do, screenshot your desktop and upload it for us all to see (lets us know if your messy or not aswell) lol.