SpeedTouchConf

Alcatel SpeedTouch USB Modem - Linux Configuration : Example Config

Here is a typical config:

Here, turing is an old laptop (433MHz / 64Mb) which has the SpeedTouch modem connected to its USB port. It has a LAN connection to the hub, which is also connected to the main systems: Elvis, the Desktop PC, and Fred, my main laptop.
The turing laptop uses this script to share the internet connection: firewall - save this to /etc/rc3.d/S90firewall, or similar.
The other machines (Elvis and Fred, here) set their defaultrouter to Turing's internal (eth0) IP address, and copy the DNS config from Turing's /etc/resolv.conf.