If you listen to a ton of music and the word "scrobble" is part of your vocabulary, you'll get a kick out of Lastgraph. It's a service that generates interesting visual representations of your Last.fm listening history. You can view a sweet line graph of your listening to a given artist, or you can generate some snazzy posters of your overall listening.

The posters are pretty huge and take quite a while to render, but you can actually print them out as some stylish, informative wall art. If you don't need something that huge, there's also a smaller version available through the quick timeline feature. You can also export your data as an Excel file, a CSV or JSON.