This is the oldest screenshot I have, from 5th June, 2004:
Yes, I did have AOL on my desktop. Don't hold it against me. It came bundled with some free download and other crapware. Never used it. IE is also on my desktop, but I used Opera back then.
And the background was rendered with Terragen.
A month later, on 27th July 2004:
Still Terragen.
A year later, on 5th of November, 2005:
Note Firefox 1.0.7 (this was just before I upgraded to Firefox 1.5). Background is a photo I took. And Skype still had a red icon back then!
Now, February 26th this year:
Yay for Google Desktop! (Also, the photo is from the same trip as the other one)
Finally, the most recent ona, from May 2006:
Which reminds me, that's four months ago. I should take another one soon.