- 120 mm computer case fan newegg.com
- 2x 120mm grills (I only have one) newegg.com - 3 for $4.99
- 2.1mm barrel jack
- 2x magnets
- 9V power supply
- Install grills
- Solder barrel jack
- Hot glue barrel jack and magnets
- Drink beers
While the fan is 12V, running it at 9V makes it nearly silent. However, it moves plenty of air. (But not too much.) I always have a 9V adapter on my desk (they are ideal for a 7805) so this is perfect for me.
The two small magnets allow the fan to stay where you put it, but the are weak enough that it can be moved with one hand.
It works great. If you have a more common 80mm fan it will probably work. It will end up being a little louder and you might need to raise it to get the air where you need it.