Turn Your Windows 7 PC Into a Wireless Hotspot – Lifehacker « Gregory Reese Research

Before we begin, you should make sure that you've got a laptop or desktop with a wireless card that isn't currently connected—if your laptop is connected to the wired network, your wireless card should be free, and we can use it to allow access to the internet. Note that you have to be plugged into a wired connection in order to share the connection wirelessly with others, or have a second wireless card. Readers should also note that this won't work on (some) work networks that use group policies to enforce TPS report cover sheet boredom and prevent you from having any fun at all.

via Turn Your Windows 7 PC Into a Wireless Hotspot – Lifehacker.