Who has/wants a short-URL catalog?

We do, at Cluetail. We want one, that is.

As we are looking at social networks, trying to analyze online
conversations, we want to know which "original" URL is behind each
short URL that we come across.

Reversely, we're also interested in knowing all the various short URLs which are pointing at any given "original".

So we're planning to build this functionality, unless… somebody has
already done it. And that's the first thing I want to explore with this

Has anybody out there built a catalog of URLs and the shortened URLs
pointing at them, which can be queried both ways: by submitting a long
one or a short one?

Secondly, and relatedly:

In case it shouldn't yet exist, would anyone find it useful if we offered such a queryable (spelling?) catalog as a service?

Why I could imagine that a service like this might add value is
because, due to the proliferation of short URLs, it is becoming
increasingly cumbersome for anyone with a web presence to gain an
overview of who is linking to them.

This tool could answer the question: "Who is linking to me?" including shortened links posted on social networks and the like.

Feel free to leave a comment below or drop me a line at <jos.schuurmans[at]cluetail.com>.