At a buck each, I bought six plus some other stuff to make the $10 minimum order.
The little fans can be rremoved from the heatsink and used for lots of things, including blowing on a hard drive to keep it cool.
This was supposed to be the "deal of the day" and good for only 24 hours... but still shows $1/each now several days later. Directron's "deal of the day" is often a GREAT find. Like the Microsoft/Dell wheel mice for $2 each a couple of weeks ago.