From: John Hines
In order for something to blow out, there must be an intake, or youwould
create a vacuum, and the house would implode.
The coolness you feel is "wind chill" from the air movement over youhand.
I've always heard them referred to as "cold air return" even whenthey are up
high and return hot air for the A/C.

Very interesting. I was just going to post and ask why it feels as if cold air
is being blown out. I guess you're a mind reader!