The Chronicle's current issue includes an examination of how some nonprofit groups are using the social-networking site Twitter to raise awareness and money: http://philanthropy.com/free/articles/v21/i09/09001401.htmAs an extension of that story, I'd like to use this forum as a place to collect a list of charities, foundations, and others in the nonprofit world that are using Twitter. Please feel free to share the name of your group and your Twitter handle -- and share some info on how you are using the tool for your group.And we won't even limit you to 140 characters.