So what was once Audioscrobbler was recently reintroduced as last.fm. It's a site that tracks your listening habits and tries to do fancy things with the data, like customized radio stations, recommendations, social networks, etc. Anyway, I'm trying it out, you can see what I've been listening to at this page.
Note: There's a feed off the site for most recently played tracks, I've put it in an iframe on the sidebar. I might try reformatting it to better fit in the space and skip the date/time information, but it might be tough without running php or jsp.
Update (8/16/05): I put a litte java code here that can just pop in to a crontab for generating the sidebar. Krufty but all I need right now with little time invested.
