Neat mod, though in my case I'm actually not looking to cool slots, but a hard drive in an entirely different part of the case, and I need a super thin blower or fan to do the job. A blower is ideal because the 90 degree angle of the air flow allows the HD to be cooled while exhausting air out...
I spent hours searching for a thin blower for an SFF case I am working on, and came up with just two in the entire world. One is an interesting "water wheel" design, but only available from one store in New Zealand! The other is more common but still hard to find. Google for "mini system...