“Aquaskipper” is a human powered hydrofoil.
It’s similar to the original Swedish Trampofoil, which is no longer available.
There’s also one called the “Pumpabike” from South Africa.
They’re also called “hull-less watercraft” and “flapping wing propulsion vessels”.
You bounce up and down to make the wing fly and propel you.
If you stop you fall into the water and swim back to the dock.
It’s completely ridiculous and works really well once you get the hang of it.
