We've got instant hot water, biggest ever waste of water if you want hot cause it has to run for a long time until you get the warm. So we fill the kettle when filling the sink for the dishes as we boil water to drink and cool it and filter it anyway.
But they shouldnt sell instant burners in Australia we have big water shortages out here!

Memphis is right I think, its all down to switching on and off,uses more power to draw current through the ass crack.