SANS Digital is pushing this steller two bay network storage enclosure with iTunes server support. Although you can home-brew your own USB drive with iTunes support and give public access to your home network, the SANS Digital MobileNAS MN2L will also do the trick.
For the “out of the box” type the MN2L has FTP support for easy access through the internet – something our home-brew version does not – along with RAID 1 or 0 settings for protection against hard drive failures. Another feather in the cap is cross platform support for Windows, Mac and Linux.
If you’re feeling spendy, this will set you back $299.
SANS Digital MobileNAS MN2L product page.