Sure, Radiohead's been pushing the musical envelope for more than a decade. But making a mainstream hit out of an atonal cacophony is nothing compared to their new experiment: selling a downloadable new album at a price listed as "It's up to you." In other words, if you think In Rainbows is worth a few pennies, or $10, or $795.26, then that's what you pay. You can name your price (in British pounds) right now over at Radiohead.com, where pre-ordering is available for the download. I think this is a great idea, except for one problem, and it's the same problem I've always had with paying for albums. How do you know if it's worth the price until you've listened to it?