Mr. Tweet will do some homework for you - although I still believe in the randomness and greatness of building a network - I often find people that I thought I was following and wasn't. I don't know how this will work, but am goign to test it out!
If you are a teacher on twitter, you can "join" this group - which means nothing except your name is added to a list. I like this b/c it helps teachers find other teachers. Wish it let you put a little info but you can look at the twitter id's - I like that it is automated even the excessive ads are a little bothersome, I can live with that -- share your id or make another group.
Great feedback from Kim Cofino from the peer review of flat classroom from her fifth graders. Having students of younger ages review the work of older students (and vice versa) is a phenomenal way to have students do work for all audiences. Kim is one of the leaders and organizers of the sounding board program.