One of the crucial tools we have used to help the revolution in Iran is the proxy server. This enables them to evade the government's censorship and continue to connect to the internet. Given the attempts to crack down on the flow of information, you can appreciate how valuable this is. And this is why the internet is making the internet is changing the nature of political resistence around the world.
Daily Kos has this excellent diary that takes you through the steps to create your own public proxy. If you are able to do so, you will keep the door of free information open for countless Iranians. The revolution needs your help!