Webjay (www.webjay.org) is now running ads for Magnatune on the top right of every page.
I've been working with Lucas (who runs webjay) to make the ads really useful for webjay users.
Specifically, the ad is a link to play a song from Magnatune, with the option to add the song to their webjay playlist, or get more info about it from Magnatune.
Of course, I'm paying webjay for this privilege, but Lucas and I have a mutual-admiration thing going on, so I'm pleased to be supporting Webjay, and I think this "advertisement" is not at all obnoxious, as it supports what Webjay is all about -- finding good music and sharing your findings with others.
For those that don't know about Webjay, it's a free service where you make mp3 playlists from legal mp3s on the Internet, and then post your playlist to webjay so that others can listen in. It's a great way to discover new music, especially if you find someone who's playlist tastes you like.