Mike Linksvayer, the CTO of Creative Commons, runs the numbers of Nine Inch Nails's Creative Commons download experiment and discovers that it only took the band two days to exceed the typical net from a massive-selling traditional CD release. The band sold $750,000 worth of "limited edition deluxe sets," plus an unknowable further sum from sales of the regular CDs and merch.
The $300 "ultra deluxe edition" of Nine Inch Nails' Ghosts I-IV, limited to 2500 copies, sold out in a couple days (I believe released Sunday, no longer available this morning). There are some manufacturing costs, but they don't appear to be using any precious materials. So if an artist typically makes $1.60 on a $15.99 CD sale, profit from sales of the limited edition already matches profit from a CD selling hundreds of thousands of copies.
Then there are non-limited sales of a $75 merely "deluxe edition", $10 CD, and $5 download, and whatever other products NIN comes up with around Ghosts.