Tim Bormans created a mashup that creates music tv with youtube and last.fm mixed together.  The Music TV mashup was also a winner on the mashupawards.com.

How the Mashup with YouTube and Last.FM works
Type in your favorite artist and Tim Borman’s program finds similar artists.  It’s about half videos, half music.  Plus, it helps you find new music similar to artists you already like.

Tim’s site describes it as “online music television based on your taste”.

How to use it?
Enter a last.fm username or music artist you like at the top of this page and hit the ‘Ok’ button. A few seconds and some funky coding later you will be watching your own personalized music channel. Now ain’t that sweet?

Link Here or Check My Most Listened to Channel