Burning Bird has a neat idea for a trackback-style system based on Technorati tags. Tagback would assign a unique tag to each blog post; followup posts (or photos or links) labeled with that tag are picked up by Technorati and compiled at the page for the post’s tag. For example, all the tagbacks to Shelley’s “introducing tagback” post can be found right here.
Aside from potentially solving some of the problems of trackback spamming, this is a pretty neat way to add trackback-like functionality to blog software that doesn’t yet have any built-in support for it, like Textpattern. All it takes is a link from each post to its tags page, and all the heavy lifting is done off-site. It should be easy to make a quick Txp plugin to create and display the appropriate tagback link based on post titles.