I came up with some PHP code that'll download the plaintext list files for a user and display it on a webpage. It adheres to the wishes of the audioscrobbler developers in that it caches the results, only downloading the file if the cached file is older than 30 seconds.

Update for 29 October 2005: My code can now display any of the text-based lists, including top artists and top tracks, along with pre- and appending text with each entry so you can turn your lists into proper HTML lists.

The code and instructions can be found at my Last.FM Info with PHP page.