Thought this looked like a good price and couldn't see it posted.
Here is the blurb
The Xbox 360 Wireless N Networking Adapter offers versatility and ease to your Xbox 360 experience. Jump into "Halo 3: ODST" or "Forza Motorsport 3" and enjoy lag-free network gaming and multiplayer, or put your media centre to the test by streaming your favourite HD movies and videos. This dual band adapter seamlessly synchronizes your Xbox 360 with the newest wireless N standard, allowing two times the range and a speed seven times faster than before. Easily stream all of your Xbox LIVE entertainment such as Games on Demand, HD movies and TV shows and music through Xbox LIVE or your media centre PC.
The Wireless N Networking Adapter provides increased speed, coverage and reliability, and features a high-performance design with two external antennas that works great with 802.11a/b/g and n connections. Simply snap the adapter on to the back of your console and enjoy wireless connectivity in multiple rooms or congested wireless environments and connect safely with WPA2 security support.