with linux you can have an AWESOME cacheing proxy server... not only will you be able to share your connection, but you'll save bandwidth and speed-up everyone's web-surfing...
the proxy software of choice on linux is called "squid"... here's the link to the website:
http://www.squid-cache.org
personally, i'm
kinda familiar with squid, anything you need, just ask...
here's some howtos:
http://www.faqs.org/docs/Linux-mini/...rentProxy.html
http://www.siliconvalleyccie.com/linux-adv/squid.htm
http://www.linuxdevcenter.com/pub/a/.../tutorial.html
what kinda hardware are you planning to use???
RAM is the most important factor when dealing with squid...
here's a few personal suggestions:
configure the machine squid runs on as a firewall, to provide security for your network, and to give more complete internet access to the client machines (squid only does
web traffic)... we can help you on this thread with this... it's done with
IPTables, or with a front-end to iptables such as
Shorewall,
Firestarter, etc... or with an online iptables script generator like
Easy Firewall Generator for IPTables...
the best way (IMHO) to run squid is in
transparent proxy mode... in this mode, the firewall automatically re-routes all
web traffic (from the lan) to the (likely local) proxy server... in other words, your windows users don't have to enter internet explorer's configuration and put the proxy server's ip address, etc... the proxy server will optimize everything invisibly behind the scenes on the gateway, thanks to the firewall's rules...
if you go for squid and a firewall (very recommended), you might as well throw-in a
dhcp server too (it's very easy), to make the whole network configuration automatic...
all you'd have to do then on the windows boxes is click on the "automatic configuration" option and you're done... the windows machines will be enjoying the benefits of a linux gateway in no-time...
here's a dhcp server howto:
http://www.siliconvalleyccie.com/linux-hn/dchp.htm
=)