#!/bin/bash

modprobe usbnet
ifconfig usb0 192.168.129.200
echo 1 >/proc/sys/net/ipv4/ip_forward
for f in /proc/sys/net/ipv4/conf/*/rp_filter; do echo 1 > $f ; done
iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE

Device Drivers -> USB Support -> Intelligent USB Devices/Gadgets
[*] Embedded ARM Linux links (iPaq, ...)
[*] Sharp Zaurus (stock ROMs)
[*] CDC Ethernet support (smart devices such as cable modems)