In a recent #mhsm (mental health and social media) chat on Twitter, we talked about the #mhm2010 hashtag used during Mental Health Month May 2010. Many organizations and tweeps successfully used it to share mental health information with a much wider network. During our wrap-up discussion on keeping momentum, other hashtags were mentioned. I volunteered to make a list and here’s what I found in use as of June 2. If you know of more, or start a new one, please leave a comment.