listen forget all the stuff you heard. i have this setup on to of my xbox's what you are looking for is two things.

an extra ethernet port(very cheap)
and a crossover cable(very cheap)

1. install the new ethernet port
2.have your main ethernet cable already plugged into you computer giving it internet accsess
3.take the crossover cable and plug it into the new ethernet port you just installed and then plug in the other end into the back of your xbox or xbox360
4. then go to Network connections and then highlight all the connections you see there and then right click them while they are highlighted and then go down to the option Bridge Connections let it bridge the connections and then your all set
5. one more thing though, the only way that you will be able to accsess xboxlive is if you turn down to medium or a lower selection on any firewall you have. if this is not met then you will not get accsess to xboxlive.
6Your finished! Now, you have internet accsess on your computer and on your xbox.
any questions? feel free to PM me im on everyday.
Cheers!

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What is a physical body. The body is merely an object. It is a form of existence far too impure to store the gods within us called souls. Now you will remember. The bloodstained history. Material desire. Hunger. Sexual Drive. Desire to dominate. Desire for fame. Humanity. As long as there is a body, desires will be born. The human ego will never disappear as long as desire remains present. Humans will continue to fight to fulfill their bodies desires and it will never end. At this rate there is no future.