After having burnt myself slightly on a heatspreader for an AMB chip on a FB-DIMM module today... first off I was surprised but secondly a thought came to my mind. Thermaltake manufacturers some third-party fans that attach to memory heatsinks and Kool Solutions also makes a cooling fan designed for the memory socket. Corsair's Dominator series also comes with a fan that attaches to its heatsink in order to improve airflow. I know there are also other products and some custom-made solutions that are available to help in cooling your memory.
If you're not familiar with FB-DIMMs (Fully Buffered Dual Inline Memory Modules), due to the Advanced Memory Buffer chip heatspreaders are a must but even still they get very hot due to the amount of heat they put out (especially when you have eight FB-DIMM modules in such a small area). Though, fortunately, I haven't run into any technical issues from the heat.
Anyways, the thought that came to me was that a stock Intel LGA-775 fan was the exact size as eight FB-DIMM DDR2 slots. After digging through a box of heatsinks, I had confirmed my thought. The stock Intel LGA-775 heatsink can was the size of eight FB-DIMM slots on a Tyan Tempest i5000XT motherboard. It fit so well that the clips used to keep the fan against the aluminum heatsink fit perfectly against the FB-DIMM heatspreaders. The fan had stayed in place perfectly and no problems while experimenting. If you are looking for a cheap way to cool eight sticks of RAM, well, this solution works fairly well. (Note if you try this out, watch out so the fan housing doesn't interfere with the motherboard PSU connections).