I don't know if this will work for you, but on CamelBak bladders I often blow them up with air, insert a wadded up paper towel and shake. The paper towel absorbs much of the lingering moisture.<br><br>Another thing to do is to use something like a plastic hanger, straw or other "device" to prop the container and mouth open (from the inside) and let it hang dry while it drips out.