Meaningtwitt is a mashup between Twitter, Google Visualization API and Meaningtool.
Tries to profile the interests of a user based on the links he twitts.
Caveat emptor: It's just a quick hack and it's got bugs galore. Wanna improve it? Just grab the source, it's MIT licensed.
It's been done by Manuel Aristarán because writing a Twitter mashup is obligatory these days.