http://www.externalpccooling.net/Page6.html
Check this out. This is a custom made external cooling system. You supply waterblocks and distilled water. Very minimal modding to case required (my case already had holes for tubing).
I have been using one for a few months. I have a 110w socket 939 toldeo core x2 4400. TCaseMax of 61c, TDP 95.0 Watts
I have a 24/7 oc of 2860 with no volts added by me (cpu in bios set at 1.35,cpuz shows my board overvolts by +4 to +6 depending on idle or load). Can go a bit higher with a bump or 3 to cpu voltage.
At this moment, I have a room temp of 30c and my cores by core temp are running 42-46c under 100% load (I crunch for WCG,2 to 4c higher when i use orthos large ffts for stability testing). For me this overclock on air at this room temp would not have been a good thing temp wise. I have not used less than the 10 ft of tubing the unit was shipped with. I could probably cut my temps a bit using less tubing from what I have been told. Installation was easy even for a wc noob like me. And as a bonus, this unit is so quiet, if not for the bling on the unit (lights and such and it does look good), I wouldn't know that it is running.
The other point I would make, Seth (the guy who invented/custom builds your unit) is one hell of a nice guy. He was available for questions and advice by e-mail and even by phone.
The price, well Seth can give you a rundown on that as he has 2 unit types to choose from. I will tell you that if you look at prices for the quality components used and shipping, it would seem that he doesn't make much off each unit.
Jim