www.deviantart.com - Largely photography and anime based, large community means lots of possible viewing but also anonimity (or however thats spelt) I mostly post pictures here first as it does not give me the same headaches as Renderosity did.

www.renderosity.com - Largely 3d digital medium based (Poser Bryce etc) though it does have a fairly well established 2d group who are willing to help if you are willing to ask things This was the first site I started posting to, however pictures started going missing which was irritating when the computer crashed and I wanted to review some old ones for referance but my own fault for not properly making backups has a 1 post a day limit now I belive (it used to be three, but it maybe changed again or maybe I rember wrong... unsure.)

www.tate.org.uk - The online base of the Tate gallerys, it has a reasonable online gallery also and gives you news on upcoming events in the various gallerys that are part of the network.

http://www.artcyclopedia.com/ - does what it says on the tin. It's a bit... crusty for want of a better term but it can be really useful when a normal search engine is just a bit to widespread in its search.

http://cellosoft.com/2draw/ - There are quite a couple more such boards as this but if you don't have a art program to call your own these kinds of boards that have applets on are great for praticeing your craft, the gallerys are also nicely open and people are more likely to view your work on an equal level than they do on the larger sites. I also find applet drawing is good for honeing skills as it gives you restrictions and makes you be more consideret in your methods. This is also the one I post on of course .

http://www.vogue.co.uk/ - I know this seems a bit random but its good if you want referance to draw from but any similar site also is good, try out dance magazines it helps with foreshortening though nothing beats drawing from life for that of course.