The Hydro Powered Jetovator,and the many other jet packs. This was popular in the 1960s I remember watching Sean Connery in one. I’m pretty sure it was in the 4th installment of Bond which was Tunderball from 1965, and Professor John Robinson jetted off in one in the TV show Lost In Space. Its to bad they didn’t make a 2 hour TV movie of theatrical release of the show it was really cool. Now why actually fly now when a drone can do all the work.