Check out this device ,http://www.goulds.com/product.asp?ID=298&MASTERID=3 , it is installed in the home water system. List price for the 4 GPM unit is 485.00. I suppose your could run your wort into it to be steralized.
Check out my favorite New Orleans Brewhouse http://www.crescentcitybrewhouse.com/beer.html the seem to think banana flavor is something special in their Weiss Beer. Quote "Smooth quality with hints of banana and cloves with a spicy finish."
New Orleans is coming back!