I've seen regular references to Last.fm and Pandora in various blogs, online searches and the like. While they sounded interesting, they remained on my 'to explore later' list until I was prodded from an email from a friend. While Last.fm and Pandora cover a lot of the same area, they each have certain strengths (as outlined in numerous and varied comparisons). Basically Pandora is a bit better for getting exposed to new music, while Last.fm is better at cataloging your listening habits and creating a broad range of recommendations and social networking connections as a result. And thanks to a nice little online code mashup (via downloadsquad), you can have the best of both worlds: a Pandora player that submits its tracks to your Last.fm account. Last.fm ProfileRight now I have Audioscrobbler plugins reporting my listening habits from my home media pc (so far only from Windows Media Player, since the Meedio MeeCharts export plugin that should do the job doesn't seem to play nice with the current audioscrobbler API. :-(), MediaMonkey on my laptop at work, Last.fm's own player, and the abovementioned online Pandora player hack from Real-ity. So about the only parts of my listening habits that aren't being data mined are radio, CDs (played in an actual CD/DVD player), and my portable mp3 player (though if I upgraded to an iPod, this too would be covered).
Still not sure how this breaks down by scary vs. cool. You can see what I've been listening to by checking out the Recent Tracks badge in the sidebar, or my Last.fm account.