I personally have one, and thing it does a decent job cooling the 360 ( only beef is with the AC adapter plug-in being too loose, and can cause the poer cable to disconnect).
There is also rumors as to another intercooler being available to UK residents...
heres a pic of what I saw. *note* someone here should recognize this
and the description
The Cooler King is the 3-in-one solution to cooling your XBox 360, connecting up to 4 media players at the same time and playing games with high definition sound and picture quality.
1. The internal fan cooling system reduces the operating temperature of the console - helping to prolong gaming sessions.
2. At the same time the Cooler King gives you the option to connect VGA, Component and S-VHS cables for high definition gaming, and optical output for digital surround sound.
3. You can also connect your MP3 player, digital camera and additional wired controllers through the USB hub multi-tap facility.
The Cooler King is easy to install just plug into the XBox 360 and go! (Comes supplied with a scart lead for connection to standard definition TV).
Product Benefits Summary
* 3 in 1 high definition, multi-tap and cooler
* VGA, Component and S-VHS connections/li>
* Optical output for digital surround sound
* 4 USB hub multi tap for media players/wired controllers
* Internal cooling system prolongs play times
* Easy installation plug in and go
* A/V scart cable supplied for standard definition TV connection