It is possable though a hub, but you will need one computer to perform all the NAT (network address translation)

The computer performing the NAT will either need 2 ethernet cards, or it will need to be running Linux / FreeBSD / UNIX

*nix systems like linux can allow a single network card to work like 2 seperate network cards with half the bandwidth.

Can windows do this ? i dont think so ?

Anyway, Set all the machines on your LAN to use static IP's
One of the Internet shareing computers's Netowrk cards should be static 192.168.1.1. other computers on your LAN should have similar 192.168.1.X with netmask 255.255.255.0 Gateway 192.168.1.1, and NameServer 192.168.1.1.

set the second network card on the shareing machine (or the virtual network card) to use DHCP.

and enable NAT and forwarding on the internet connection shareing machine.

Provided the the NAT computer is turned on, the other computers wil be able to share its internet connection.

If you have an old machine lying around, these are perfect to turn into dedicated NAT routers / proxy's / firewalls.

no, you're right, windows can't do that. i tried god knows how many times to get it to work like that, called networking services, they weren't enthusiastic about the idea, but they tried and failed.
So similar to yours, what i did eventually was buy a second NIC, which only costs a couple $, and set the one connected to the broadband as 203.x.x.x, (the cable modem IP) with a default gateway of 192.168.0.1, and the other computers use DHCP to assign Ip addresses. they all work fine, and i get the same bandwidth from each of them--contrary to what i was told before, that the main computer would suck up more than half and then the rest would be split between the rest of them. One thing i wasn't able to do though... get 2 computers directly conencted to the modem. one through LAN and one through USB.

The easiest way to share the broadband connection is to use a router. I use a Linksys broadband router with built in 4 port switch and wirless access point.

If you setup one pc with a modem and share the connection with the rest of your network then that pc has to be on all the time which defeats the object of having your internet connection shared, why not just use the one that is switched on.

If you setup a pc to act as a router then you lose the functionalaty(spelling???) of the pc.

A good broadband router with builtin wirless access point costs less than £90 so it makes sense to go with that option and it means that you get all you DHCP and firewall need done for you.

I think :
-go to control panel
-click Network Connections
-right click on your local area connection (or your connection)
-click advance menu bar
-click setting
-and then tick to the off menu, then click ok
-click allow other network users to connect through this computer's Internet connection
-click allow other network users to control or disable the shared internet connection
-click ok
-DONE!

or if you cannot do it, I am sorry but I can fix it with this method

I use a simple setup at work.... ADSL Trought a CPU Gateway/Firewall (Win2k ICS Machine). Since i have a Speedtouch 510 (4-port router), with a buited-in firewall, my network is safe and my web access is very fast (4Mbit).

At home i use ICS on Windows XP to give internet to everyone.