OCModShop posted a review on the CoolIt Systems PCI Cooling Booster
A quote from the article:
CoolIT Systems PCI Cooling Booster Review
Most PCI and other expansion cards do not generate alot of heat, and therefore are overlooked when cooling your computer system. Today's multimedia and home theater systems include high performance TV tuners, video capture, and high-performance sound cards that do tend to get quite warm, and could benefit from additional cooling. Even many video cards could use some extra help, as the tiny OEM heatsinks are either underpowered or fail.
If you want some additional cooling insurance, then CoolIT has the solution for you. Their PCI Cooling Booster product is intended to fit right over the PCI bay of most motherboards, thereby providing additional airflow between your expansion cards and cooling their internal components.
CoolIT Systems PCI Cooling Booster Review