I wrote a USB over IP system for several platforms including openwrt. Sorry its not open source but it is free to share one device. Its mainly useful for OEMs who want to provide usb sharing functionality from their routers.
The server runs entirely in userspace, and the client runs on windows xp+ and osx 10.7+...
You can download the server from http://www.virtualhere.com/usb_server_software
and the client from http://www.virtualhere.com/usb_client_software
Give a try and see if you find it useful, at the moment it is compiled for AR7xxx/9xxx and x86 but i can compile it for other platforms.
(Last edited by msbroadf on 28 Jan 2014, 04:26)