This is a little dated but Addonics has introduced a NAS adapter. It has an Ethernet port and a single USB 1.1/2.0 port into which you can plug, presumably, any USB drive or printer and access it over the network. It can supposedly be accessed from any Windows, Mac or Linux platform, although their site says Linux 2.6 and above and also can be an FTP target.
$55 from ShopAddonics.com, presumably cheaper elsewhere. I may have to pick one up just to play with it.