Yep, several people have tried it. Just make sure that your cooler is stainless steel. If you use aluminum, make sure you only use sodium bicarbonate as your electrolyte. KOH and NaOH both eat aluminum in just a couple of hours.
edit: I should note that several people believe that sodium bicarbonate (NaHCO3) breaks down into CO2 gas and NaOH, at which point it will eat your aluminum. I haven't tested this theory out yet, but it is possible.
--
Some days I get the sinking feeling that Orwell was an optimist!