I bought a Scythe Kama Stay multi-purpose solution. Its purpose is to hold a 120mm fan to cool the graphics card. With the fan being so large, it actually cools both the video card and the Northbridge heatsink. Attaching 2 – 120mm fans to the Scythe Kama Stay multi-purpose solution, it can also work as a graphics card, Northbridge and Southbridge cooling system. Unfortunately, since the fan is not touching the heatsinks, it will not cool as well as a running fan touching the heatsinks. Although, it seems to be doing a pretty good job nonetheless. I am pretty sure that this is much quieter than any 40mm Northbridge fan available. The system configuration and the test results can be seen at http://aprivatebeach.com/blog/2009/11/custom-silent-pc-nov-2009/.
The Scythe Kama Stay is also reusable on future computers. It is not a card that plugs into the motherboard like the video cards. Therefore, it is quite possible that it can be reused over and over again on future computers. Unless one decides to mangle it to the point where it will not fit in the case.
For those that want to replace the Northbridge heatsink with a taller version, this may work http://ncix.com/products/index.php?sku=10205&vpn=ZM-NB47J&manufacture=ZALMAN%20TECH.
Thermaltake has one that is compatible with both the Northbridge and the Southbridge. It can be seen at http://www.thermaltakeusa.com/Product.aspx?S=1231&ID=1901#Tab0
Since the Scythe Kama Stay can hold 2 – 120mm fans, it is quite possible that it can also hold a 240mm fan. If this is possible, this can be used to hold a 240mm fan that will cool everything on the motherboard including the CPU. Although, the CPU must have a fairly large heatsink that can support a fan on top and not the sides. Unfortunately, there is no mention of the Scythe Kama Stay supporting a 240mm fan.
The Scythe Kama Stay multi-purpose solution can be seen at http://www.scythe-usa.com/product/acc/071/sckst1000_detail.html and being used below. It is cooling both the video card and the Northbridge.
Finally, there is always the liquid cooled solution. Unfortunately, that is usually too expensive for most people.