I've seen very stupid cooling solutions, including BFL's take on that matter.
It's quite well known that cool air is heavier than hot air.
Hot air always flows naturally upwards.
The Jalapeño pushes cold air from the top and pushes it downwards to the other side's venting.
But that's not even close to smart...
In Jalapeno cold air is pulled from the below intake, pushed upwards and vented through the upper exaust.