There's a micro-jet in James Bond: The Man with the Golden Gun (I believe it's that one) during the opening sequence. It's 9 feet long and has a 13 foot span, flies 300 mph, and its engine is the size of a large briefcase.
This aircraft actually exists and still flies today, doing stunt routines in Nevada. It has a crew of one and no passengers.
I have also seen nano-jets that are litterally the size of a pin-head. They are purely experimental at this point and are designed to power tiny aircraft that could fly unnoticed into open windows and spy on bad people, or to propell small craft that are to "swarm" with insects.
Those who fail to learn history are doomed to repeat it in summer school.