Songza: Minimalist music search
Songza is a new music search engine and player. It's got the cleanest interface to a music library that I've ever seen, and it's great fun to use. It is limited, though.
To play music on Songza, you just type in the band or the song name, and a list of results pops up. From the list you can play tunes directly, or queue them to your playlist. You can also share the track, either by e-mail or with HTML code you can embed on your own Web page.
It's like Google for music.
All of Songza's music comes from the YouTube API. Essentially, Songza is just an audio player for the YouTube music category, and when I first saw the site I thought it couldn't be legal. Songza's Scott Robbin assured me that the site sends a lot of traffic back to YouTube, and that clicking on the "buy" link on a track redirects to Google Checkout. This is true, but what Checkout displays and what YouTube plays may not be the same. If you're playing a cover of a track and you click "buy," you're likely not going to see the cover as the first track listed in Checkout.
Robbin told me that the Songza developers are, "Working on integrating Creative Commons artists, linking back to them so they can get direct sales."
The project is being run by the development company Humanized. Robbin says, "We think it does a good job of conveying that there's life beyond the hyperlink, keeping a clean interface while providing rich functionality." He's right about that. It's fun to use and the interface is both creative and functional. If you like Songza, though, you might also want to check out Seeqpod (see Eight music players compared), which while not as beautiful, plays tracks from more sources, which makes it a better music jukebox in the sky.
Rafe Needleman writes about start-ups, new technologies, and Web 2.0 products, as editor of CNET's Webware. E-mail Rafe. 
beautiful design and possibly legal (if they push off the copyright issue to youtube) but playing the music on their site might make songza liable also.