The Heinz Beanzawave, which measures just 19cm tall by 16cm, doesn't even need to be plugged into an electrical outlet.  The device contains a USB port, so mid-afternoon snacks can be heated up on from the convenience of your office desk computer without expending excess power.  Heinz claims that snacks can be warmed in under a minute thanks to intense heating action from a combination of cell phone and radio frequencies.  Unfortuntely you cant rush out and buy one as currently its only at the prototype stage.