I've posted it a couple times in the Chili thread, but it's extremely hard to beat the value of the clearance
Antec Kuhler ShelfMy cooling setup uses two of them (one as a backplate/VRM fan) cost a hair over $25, and it works stellar. The bottom one keeps the ASICs pressed nice and tight against the actual heatsink, and makes a great stand to hold the board up.

THANK YOU for posting this. I have been working on boosting Jalapenos with extra chips and cooling on the board; I found that running a copper heat sink on the bottom of the board provides as much cooling power as the stupid AL one plus fan does on top.
Currently I am running 5 chips, 65c temps, thinking about going for 6. The JP's 1 volt supply is only rated for 80amps or so and I think if I go over 6 we will be screwed. How big/high power is the DC-DC 1 volt converter on your device? Did you need to go over 100a?
Thank you again. Here's a pic of my latest.. project (20gh)

I'll order one of those heat sinks for a better top one. Then I can go to 7 if I can backfeed the 1 volt supply/based on your thoughts.
Chris