I've long wanted a place where I can collect all nice costume pictures without having to download them all into my computer. I considered tumblr-blog, but you can't really organize the pictures with that.
Then I found Pinterest. It's like an online pinboard. And you can organize pictures anyway you like.
You can find my boards here. I started with just a few boards and now I have 28. I have own boards for costumes from different eras, for fashion plates, for period photographs, for movie costumes, etc. My primary objective with Pinterest is to collect pictures I find inspiring for later use. It's also good with sharing and I follow a bunch of people there, who post pictures I like.
Do you have a Pinterest account? I can sent an invite if somebody would want one. Not sure how it works, though, if you get to join right away or if you do have to wait.