If you're not familiar with the Live Search homepage at www.live.com, you should really check it out. It took a long time, but the Windows Live team finally got something out that really looks better than what you'll find on other services. I've always been a fan of the holiday themes Google and Yahoo use, but with the images on Live's homepage, I have to say there's a much better, much more interesting experience. The image changes daily and it comes with 4 or 5 regions of the image that provide some searches related to the image... usually. Sometimes they're a bit off, but other times, they're absolutely great. My favorite was the one from election day. There was a very cute section that said, "U can haz kittenz instead of politishens." Hillarious.
I try to check out the new image every day because they're very nice. I just wish I could save some as my desktop. I also wish they'd archive and make them searchable. I did talk to someone on the team, however, and it sounds like they're looking into both of these options. The issue is the licensing agreement for use of the images. Hopefully, we'll see an update to this soon. Until then, keep a look out for the latest image of the day!