I've written here before about the potential benefits of people joining Twitter (twitter.com) as a tool to share more than just trivial information about what you're eating for  lunch or your random musings while in the line at the bank.  I have met many remarkable people through Twitter and learned an incredible amount of very timely information from what I've seen in the "twitter streams" from people and organizations I follow. I also use it to share the latest results in real time on important trials being presented at medical meetings.