From LP, to cassette, to CD... to USB flash drive?

The Barenaked Ladies are releasing their newest album, Barenaked on a Stick, on a 128 MB USB flash drive. The $30 drive includes 29 songs in MP3 format, photos, videos, and much more. The drive can play on PCs, Macs, and a lot of the newer audio equipment like some car stereos that have a USB port built-in.

For awhile now I've wondered what - if anything - might possibly supplant the CD as a medium for offline music purchases. I'm still not sold on buying my audio online: call me old-fashioned but I like having something tangible that I can hold in my hand for my money. It's way too early to see if this is really going to be a serious threat to CD, but this is still a pretty neat idea that the Barenaked Ladies have hit upon.