I first thought of this one http://www.aerospaceweb.org/question/aerodynam ics/q0130.shtml
only 10 though they're all jet engines and the 'plane' weighs 540 tonns. It doenst fly in the normal sence but uses ground effect to gain a little lift and low drag (see web page)
Must admit hamish that I had thought of looking for a picture of the Russian Ekranoplane (known as 'The Caspian Sea Monster'), but thought this probably did fit faith's question, as strictly speaking it is not an aeroplane.