Movable Type‘s Trackback feature was implemented with a “let’s throw this out there and see how it’s used” attitude. Of course, with Movable Type’s loyal user base, I’m sure Ben and Mena were quite sure that they’d be seeing unique and innovative uses of Trackback within weeks.

Blogroots has one: Blogpopuli, a blog about blogs by bloggers. How’s that? It’s a community blog based on Trackback functionality that allows bloggers from all over to contribute to that section of the web site. It’s one of the early examples of how Trackback may evolve in the coming months.

Stuff like this is what makes keeps me excited about the web.