[Rabidsquirrel]

http://www.lowes.com/lowes/lkn?actio...140&lpage=none

I'd do two or three of those, and have each hooked up in its own zone. You don't want to run all three if you don't have to, and one will turn over most of the room in 15 minutes. A bit pricey, but I'm sure you can find something cheaper.

I'd be worried about the sound levels generated by something any larger.

Here's something at 300 CFM:

http://www.rewci.com/300-cfm-deluxe-quiet-exhaust.html

Here's more:
http://www.rewci.com/dequexfa.html
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