Pinterest

What a cool website!  I can go all over the web looking for cool pictures and other things that interest me, and "pin" them up onto boards that I specify.  Not gonna lie, interest feels really girly to me.  maybe that will change as the website gets bigger.
I think that this website has a lot of great potential for students to learn, it's a great place to find quality photos, possibly for group projects and things, also a great place for me to ask my students to tell me about themselves.  I could see their pinterest boards and know a little more about them that I might have known before.  In that sense, Pinterest is  a great get to know you tool.  I could also have them post pictures with captions that show what they've learned about the picture, or the person in a picture for a review game, or study help.  I could have them review my boards with captions underneath to help them learn, possibly like flashcards or something.
Difficulty might arise in having them go looking around for pictures on the internet.  That is getting more and more risky.  But all in all, it's a great technology, and fun to work with.