If you're not on Twitter yet, and you want to help those risking their lives in Iran to get information past the government:

1. Start a Twitter account at twitter.com. It takes about five seconds.

2. Email me to find out who to follow once you're there, and how to follow them. Not posting Iranian usernames publicly is one of the rules of this game. The Iranian government is trying to find the people who are getting the information out.

3. Read this while you're waiting.

It's OK if you don't know what Twitter is yet. It will become clear that all it is is a way for people to say stuff to whoever's listening. They have a limit of 140 characters. Usually it's dumb stuff about what someone's eating or listening to, but it's become the main source of on-the-ground information about the situation in Iran.