My most desired Tumblr feature: a button in my Firefox toolbar that says “Add to Tumblr” that will let me follow any site using the Tumblr interface, as well as allowing me to heart and reblog whatever I want. Pretty pls?
I seem to recall somebody making a hacktackular version of this: bookmarklet figures out the appropriate RSS URI and submits it to a little DB, a little script periodically polls that DB of feeds and posts them to a Tumblr account set up for that purpose. By following that Tumblr you get all the content from those various sites.
Hm. Anybody else remember that and have the reference? If not, I might need to build it…that would actually be really, really useful.
Update: Ah, I see a number of gotchas lurking in the project, but I’m intrigued regardless. Need to think about this a bit more.
Also update: superfeedr!