Not technically mine, but my Dad's (which is in my garage and he has no liscense) 1965 Honda 65. Its not in as good of shape as this picture, but its not horribly far from it. I've ridden it a few times. Its currently not running though.
Technically my smallest bike would be my current and only bike I've ever owned, a 1981 Honda CM400e. Its also not currently running well.