Open Source Tagging Engine


As part of a other application we need a tagging component. However
instead of just duplicating the ‘known’ social bookmarking tool we want
to extend the way people tag there pages. Let me explain by giving you
an example: “When I like a book on Amazon, and I tag the link, I want
the application to ‘fetch’ as much information as the Amazon (or other
web 2.0 api’s) can give me to include this. So amazon could provide me
with the best title to use (instead of using the page title), tags,
rating, licence of content, enc. I could just display a simple title,
description, tag in the list but on mouseover a diaglog could apear with
the ‘extra’ information amazon provides me”

So what we are searching for:

* A initiative (or standard) that provides a standard way of letting
  applications tag there content (I looked at microformat enc, but
  could find something).
* A way to add connectors to a rails application thru a web
  interface without risking hacking attempts

It will be a MIT licenced rails engine using