Make computer act as WiFi-Ethernet bridge?

[Xero Xenith]

Essentially, I have my Internet connection on Ubuntu handled by a USB wireless adapter (wlan0), and I want to share this connection with my Xbox 360 via Ethernet (eth0). Is there a foolproof way of doing this that won't interrupt or be interrupted by downloading or web browsing on my computer?

Thanks very much for any replies!

[Iowan]

Here is a help page on internet/connection sharing. Near the end is a link on wireless sharing that sounds like what you want... but dunno if it is foolproof, or immune to "interrupt or be interrupted by downloading or web browsing on my computer"