The Nyko Intercooler is a possible solution, since it keeps your xbox cool. This cooling unit plugs into the back of your 360 using the 360's power supply. However, there's an ironic problem. The Nyko Intercooler is also badly designed ... and also melts. The problem is that the 360's power supply at times uses so much juice that the Nyko's adapter melts.
Also, because the 360 wasn't designed to power a separate set of fans, it sometimes does not get the power it wants and games crash. Bummer! (happened to me within 5 minutes of use without this mod).
The obvious solution is to rig it to use it's own power supply! My method involves getting an AC/DC adapter so that you can get juice from your wall. I found another design that uses 12v batteries. [link]
http://forums.xbox-scene.com/index.php?showtopic=602647&st=0[/link]. I personally prefer my design, because you don't need to worry about getting new batteries all the time!
Step 1: What You'll Need
The Nyko is set up very simply, it's just 3 fans all wired together. However, you may need to do some very simple calculations to get the correct power supply.
I = P/V
For 12v you'd do this: (1.44 * 3)/12v = 0.36A
In other words, if you use a 12v power supply you should get at least 360 mA. You can get one at radioshack, and those two numbers are blatantly visible on the packaging. I used a 9v, and for that you'll need at least 270mA. I'll assume you'll get a 9v with at least 270mA for this instructable.
Thanks to my pal Joe for helping me with the math. Anyhow, I managed to run this on 3 AAA batteries so we based the math around that.
Tools and Supplies
Wire (I used thin wire wrapping wire)
handsaw that'll cut plastic
9V AC/DC power adapter with over 270mA
Female adapter for that power supply (device specific)
Phillips head screw driver
Wire stripper (you can use your teeth)