The best fans by far for 80mm are the <A HREF="http://www.thermaltake.com/products/dcfan/a1214.htm" target="_new">Thermaltake A1214</A>, a.k.a. the Smart Fan, and the <A HREF="http://www.thermaltake.com/products/dcfan/a1357.htm" target="_new">Thermaltake A1357</A>, a.k.a. the Smart Fan II.
The A1357 for example runs between 20.55 CFM and 17 dBA at 1300RPM at the low end and 75.7 CFM and 48 dBA at 4800RPM. There are not any other fans in the 80mm range that can beat them.
If you don't have access to buying one of them. You can use the Panasonic, Panaflo, FBA08A12U1A with a rheostat and drop it down to 2950RPM to get 39.6 CFM at 32 dBA. (100 grams, Min - 7 V = 24 CFM and 21 dBA, Max - 13.8 V = 46.9 CFM and 38.2 dBA. You can use the Paspt if that is all you have access too.
<b>"If I melt dry ice in a bathtub, can I take a bath without getting wet?" - Steven Wright</b>