yea just wire up an intake fan and and exhaust to a cell phone charger, and your set. thats the quietest you'll get.
except for blowing with your mouth-kaiserAxel lol
and ya im going to use a computer fan but want to know if there is a certian kind or one that works the best as i will be needing it for my rubbermaid box grow so dont want a fire or anything.
id go to home depot and buy a regular circular fan they arent to noisy ..... but if you mean like intake an outake fan the industrial fans are very loud i use one for a carbon filter and a large one to suck out the hot air of my 1000w lights.... those you can hear pretty well even with a door closed.... squirell fans are loud also