While it may or may not be true that if everybody had an ocean they’d be surfing like California, it is true that with a water pump, some copper tape, and a few scraps you can make a surfing simulator that sprays you if you don’t keep your balance.
You can see the simple device in operation in the video below. We presume [Adi_10] actually surfs, but we can’t comment on the realism of the simulator. There’s no computer. Just a switch made from the base and the balance board.
As projects go, this is pretty simple being little more than a pump, a battery, and a switch (although the switch is, of course, the crux of it). However, it is a good reminder that not everything needs an Arduino or a Raspberry Pi. It would be a fun project to do with kids to get them thinking about building hardware.