This simple method seems to get the thumbs up from the brewing community on at least one forum. Personally I couldnt be f#@&ed, yeast is cheap. Having said that some time in the future Im keen to try n capture a wild yeast from the local cane fields for my Rum ferments, If that venture turns out OK, I will then try this method.
http://www.homebrewtalk.com/f163/yeast- ... ted-41768/