Recommendations for a photo reference website?

[megas_imperius]

I've been looking for a good place to find photo references for things like animals and clothing, but so far I haven't found any that are really worth looking through.
Can anyone recommend a website with lots of good images that are well-organized?

[Ellingsworth]

Not really helpful if you are looking for nudes to draw but for clothing and poses this should be perfect for you. :)

http://usemycomputer.com/

EDIT: Another awesome site.

http://www.sxc.hu/

[Elwell]

Have you tried the two big stock behemoths?
http://pro.corbis.com/
http://creative.gettyimages.com
Preview images are smallish and watermarked, put perfectly adequate for reference, and the search functions are excellent.

[tensai]

also really helpful if you don't want to have that perfect composition etc. but something more natural:

flickr (http://flickr.com/)

very good as an addition to corbis et al.

[kev ferrara]

www.morguefile.com