[URY914]

I use flickr (link at the bottom of this post). Easy to use and free for the first 200 pictures uploaded. They are owned by Yahoo. You can join groups and favorite others photos. You can hide your photos or restrict them to only friends allowed to see them or share them with the public. I've been contacted from folks around the world to use my photos in books and websites.

I would think most photos sites offer the same things.