Scott Watermasysk added a comment on my Full Content RSS Fragments post, describing how he is generating RSS dynamically using etags. I fired up Syndirella + proxytrace to observe how the etag contains the date/time of the last update, which is how he knows which entries to include in the RSS document he returns. Its a great idea but unfortunately not so applicable to Movable Type because that uses static files.
Speaking of Syndirella, I switched to this aggregator from ChannelBuddy yesterday. Following in the footsteps of every man and his dog I want to tinker around coding my own aggregator, or rather the cool ideas I've got which haven't been implemented by anyone else yet, and Syndirella seems a good starting point for this. I've already forked off my private version and made minor changes to the UI according to my own preferences, i.e. making it more like ChannelBuddy (after a year of using ChannelBuddy I'm pretty set in my ways regarding aggregator UI). Its about time I did some WinForms coding and the features I've got planned should bring me up to speed in that area of .NET programming.
 ChannelBuddy is a great 3-paned aggregator, developed well ahead of its rivals but unfortunately never released. It now has only one user.