Twitter is a popular micro-blogging service that lets you post short messages (up to 140 characters, similar to SMS) so that your friends and coworkers (technically called "your followers") can receive real-time updates. You can post Twitter messages (or "tweets") via the Twitter website, SMS or through third-party applications.
Twitter is mostly used for sending social messages, but the promise of real-time message delivery to a large group seems useful for business use. Here are some ideas:
Simple knowledge sharing: It's tedious to write up an entire article to share your knowledge with your coworkers. For simple facts, posting to Twitter works just fine. Check out my tech tweets at Mister Tech Blog on Twitter.
Gather feedback: You can post a question on Twitter and get your coworkers to respond with short tweets.
Real-time info updates: During a crisis, you can use Twitter to broadcast real-time updates. Take a look at the tweets on the H1N1 Flu.
Automate your tweets: Twitter provides an Application Programming Interface for developers to write programs to send tweets or to act on tweets as soon as they appear. For example, I can write a program for my mobile phone that will automatically post my GPS coordinates as tweets, so that my coworkers can locate me instantly.
As with any internet-based service, you should be careful when sharing any personal or company info on Twitter.
So here's my Twitter feed, you may follow me to get short tips about gadgets and technology. Please drop me a tweet if you would like me to cover any particular topic.