I had lots of suggestions for people to add to the Boulder tweeters' list, so to give it a more permanent home I've created http://bouldertwits.com/. Let me know who I've missed.
I spent a couple of hours turning it into a data-driven script, so now to add people I just need to edit a csv file, making it a lot easier to update. I'm also quite proud of figuring out how to implement a one-click follow button for twitter, keep an eye out for a post on how that works. Or just look at the source if you're impatient