I think a really great startup business (great both in the sense of a potential moneymaker and in the sense of a benefit to myself as a consumer) would be a bloggable music download pointer service. What I mean by that very unbecoming name is a service which would allow a blogger (or anyone else, for that matter) to log in, find a song or album that is for sale on the web at an existing service (Napster, iTunes, Walmart Music, Yahoo Music, etc.) and produce a link that they can then copy to their blog, website, email, etc. When the link is clicked, a window pops up and streams a song or a portion of a song (hopefully the pop up is small, unobtrusive, not laden with flashing advertisments, and generally works well), and links the listener to the download service where they can download the song, album, etc. for the going rate.
The key would be for the service not to sell anything beside the advertisment, and not to host any of the content - all of the streaming media, album art, etc. should be drawn from the selling service's site.
I think the service could easily make a few cents off each song purchased that way, and perhaps they could even offer a penny kickback to the person who created the link and drove the traffic their way.
I can imagine this service getting a lot of usage from bloggers who want to say with each post, "Look what I'm listening to!"; I thought of it as a way to add soundtracks to the stories I write without illegally posting mp3's.
Any takers? It's a free idea!