There's some amazing news coming out of Iran's disputed election unrest via Twitter. It all needs be taken with a grain of salt clearly, as anyone could be posing as an Iranian on Twitter, but even still it's a unique window into this situation.
There's a few accounts I started following this weekend that I've found particularly interesting - many of the Iranian election accounts have become a swamp of re-tweets* but the following accounts have been posting links and commentary that is largely original.
In addition to these, there's also the #IranElection and #IranElections hashtags, though these are so busy that they are the equivalent of drinking straight from the hose.
* If you're a Twitter novice, a re-tweet (or RT) is a repeat of a tweet that someone else made, allowing your followers (who aren't necessarily following the original writer) to see a tweet of particular significance. Example here.