FriendStream is an implementation of @dougw's Application Idea #2 – an auto-refreshing view of your twitter friend stream. Depending on how many API requests your twitter acount has per hour, the view will refresh between every 5 and 60 seconds.
FriendStream is written by JD Maturen. It is built in Python, hosted on Google App Engine, and open source under an MIT license. Get the source thanks to bitbucket.