It couldn't look more 80s, but this Giorgetto Giugiaro design was actually actually shown at the Turin Motorshow way back in 1971.
People loved it, so by the time thw 1972 Geneva show came around they'd turned into this fully-operational road car with a 310 bhp 4.7-litre V8 engine.
It was something of a rolling billboard for Maserati, but for whatever reason they never got round to a proper production run. This is it, so if you want it, get yourself to Bonhams' Pebble Beach sale this August.
Some more pics.