There was a time where I was really, really, really into Flickr. I might go so far as to say that I even spent more time on the photo sharing website than I did on Facebook. It was a time in my life when photography was really new and exciting...and unfortunately I was living in a country where taking photos in public was sort of asking to make a spectacle of yourself. So I did a lot more photo viewing than photo taking, save for self-portraits.
What I discovered was amazing untapped talent. Some of those people have made it by now, some of them may have left photography altogether, and some of them, like me, are probably still trucking along, improving their craft all the time but not with much recognition. The world's best unknown artists reside on Flickr.