Nice layout Bill.
I messed about with blowers (impellers, actually) for a bit, but could never get them down below 25dB or so.
I've been meaning to get a larger diameter one - like this one
just to see how slowly I can throttle it down to - and how noisy it'd be at that point.
It's not the $14, of course, but the fact that it'd probably end up gathering dust alongside all the other stuff that seemed like such a good idea but that wasn't quiet enough...