This Pdgin plugin displays information from your Last.fm / Audioscrobbler profile in your user info on the various IM networks Pidgin supports. The most important information might be the recently scrobbled song.
I just fired out a new version of the plugin, still written in Perl. It is a release to make waiting for the rewrite easier for users and implements new features like the Last.fm 2.0 webservices (allowing more users to retrieve data) and more info sets that can be displayed.
Go mad testing!