Serious question - why? What benefit (besides looking cool) do you get from this, when there's no standard extension for feeds (.xml, .rdf, .atom, etc.) and lots of FeedBurner feeds with no extension at all?

Still a cool hack, though, Kris. :-)

Thanks Josh!

I started to write an explanation last night but I deleted it.

Then I turned my comment here into a full blown post. I will update this comment with a link . . . or you could just check the feed ;-).