OOh, I like! I assume it’s bigger than that though, right?
Well done, MisterRik, on those screencaps! I had a ton of those before my harddrive died. 
I have a new one now. Thank you, Omniscient, for the link to that site. So many cool shots!
I don’t know. I don’t have a desktop. 
Actually, I have some photo of the milky way on my mac, but my main machine has no desktop at all and is pretty much always running stuff in full-screen, (I use ion, which looks like this) so I wouldn’t see the background anyway.
mine is a liger named patrick. he is gorgeous.
mr buttons, check and see if there was a hurricane with your name. a friend of mine is a fran and she has a fantastic pic of hurricane fran at the height of her hurricane glory. it filles the screen.
This, taken by me in Belize.
tyvm 
Mine is Progeny 2.0, just shy of 13 weeks gestation. This is a cropped version of the photo–the one on my desktop has all of my personal information left in it.
Okay, I know it’s not a kitten…but everyone say “Awwwwwwwwww!”
Mine was taken last year near Lisbon. It has boats and stuff.
Our wallpaper is this shot of the Manoa Valley in Honolulu, Hawaii.
I took it during a visit there four years ago, from the Hale Manoa residence hall of the East West Center (a federal research institute), on the University of Hawaii campus. The nearer buildings are UH or East West Center; farther out is off-campus residential.
Way back when my future wife and I were UH students, she lived in that first building in the lower right corner, with windows. That’s the East West Center’s Hale Kuahine residence hall. I was living in Hale Manoa myself at the time, and she later changed to Hale Manoa, too.
If we ever live in the US again, I can’t think I would want to live anyplace other than Hawaii, and the Manoa Valley would definitely be a top pick.
I’m using The Tower of Babel by Pieter Bruegel the Elder.
At full resolution there are lots of little details to look at. You never know what’s going to peek out between the windows.
I’ve got a shot from Chiho Aoshima’s City Glow. She’s used the images in several installations, but the DVD version is now part of the MFAH’s permanent collection; previously, it was only a loan.
Five big monitors are lined up to create a giant animation that runs for 7 minutes, then starts again. With sound! It’s an endless loop of cuteness & weirdness–with a bench for those who wish to give it full attention.
I’ve got a wallpaper folder that has 1,617 high res photos in it, and I rotate them every 5 seconds. Some are photos I’ve taken myself, some are from Interfacelift, Flickr, Webshots, Google image search, etc. Probably some photos are from previous threads like this! If I see a pretty picture and it is large enough to make a good wallpaper, I right click>save.
99% of my wallpapers are pretty landscape shots, and when I need a minute’s escape I just watch my wallpapers cycle through and daydream about being wherever it takes me.
My desktop changes every 15 minutes, because I’m just that sort of nerd, but this is the wallpaper of this current moment, uploaded in its raw form in case anyone would like to use it for themselves. It’s a long-range satellite view of Hurricane Rita. Ah, and it just changed to an outer space view of earth, I’ll throw that one online too.
This lovely picture of two big, fluffy dogs* enjoying the snow.
*Or as my brother said upon seeing the desktop, “Those are cool polar bears!”
I like to take close-up photographs of flowers. I have set my desktop to pick one one out of over a thousend of different pictures and to change desktop picture every 15 minutes. The screensaver plays around with the same set of photographs.
current: Mermaid by John Waterhouse (possibly NSFW) John William Waterhouse: A Mermaid - 1901 « Paintings
I’ve used these as wallpaper in the past:
Orion Nebula detail from Hubble http://hubblesite.org/newscenter/archive/releases/2006/01/image/i
Carina Nebula from Hubble APOD: 2009 May 24 - Carina Nebula Panorama from Hubble
I use this Hubble image.