I found this program Magentic a couple of weeks ago and I love it. I'm sure there are others out there like it or even better but I've never seen them. Here's the wallpaper I'm currently using. I have it set to change every hour.
Office - A pic of Hakeem blocking Jordan with the phrase "Debate Settled, no finals showdown required" that I lifed from the Motivational Poster thread. Home - p*rn
A photo of a snake charmer on the side of a street in Bangalore, that I took myself. Not knowing how to keep my own photos from being linked, I'm not posting it, but it's a great shot.
At work, it's a picture of me and my two sisters at my nephew's 1st birthday in February. At home, it's a picture of Lance Armstrong and Matthew McConaughey after the Rose Bowl. Probably going to update that to something Astros related tonight.
I've been using this one of Pyramid Head from the Silent Hill movie for a while: http://img126.imageshack.us/img126/8175/pyramidhead2xq2ib.jpg And if the movie sucks, I'll switch it to something else...like an Oblivion screenshot or something.
Office - a pic of my daughter, two weeks old, in a pink "I Love NY" onesie. Home - pic of my wife and I at Angkor Watt in Jan 2004.