I used an Antec notebook cooler on my DTR laptop... the DDR2 RAM underneath had no active cooling and so the machine was borderline on being to warm to even keep in my lap comfortably... and forget about being anywhere near the RAM modules.
Unfortunately Antec's notebook cooler was pretty cheap, and the fans wore out in just a year. Due to their warranty policy I didn't have the receipt (nor could I get another) from where I originally bought the thing,
This combined with the build quality on their cooler (and what I've seen of other notebook coolers) has pretty much left me with the impression all notebook coolers are pretty worthless, even in situations such as mine where it had a large impact on cooling the memory modules I no longer consider them worth the money. Most laptops today tend to run much cooler, especially the power efficient ones, so they especially aren't needed.
Core i7 4770k 4.2Ghz
Crucial Ballistix Sport LP 1600MHz 32GB
EVGA GTX 480 HydroCopper FTW
ASUS Xonar DX
Corsair Neutron GTX 240GB | Windows 7 64-bit
Apogee XT + MCP655 & Thermochill Triple 140mm Radiator
Corsair AX1200 PSU | Cooler Master HAF-X