Entries Cache Plugin
This plugin is derived from Rael’s entries_index plugin. The original plugin would store the original modificate date for story files, so that you could later edit a story without changing it’s original date.
This plugin is like entries_index on steroids.
In addition to storing the original date, it caches all of the stories and their dates, in order to help speed up blosxom (which would otherwise have to scour your datadir each time it loads.) Once an hour (or any time interval you choose), it will rescan for new/deleted files.
it can also read and store the date within meta-data, if you like to do that (this allows you to move story files between categories, without losing the date info.) This meta-data can be in a human readable format, which is also handy.
Pretty handy, if I say so myself.