Jet power is coming to surfboards and other personal watercraft. WaveJet has designed a jet propulsion system for surfboards, kayaks, SUPs, lifeguard rescue boards, etc. It’s lithium-ion battery charges in a standard eletrical socket and the company claims it will give you 20-pounds of thrust (making it, say, 2-3 times faster than a human-paddled surfboard) for up to 30 minutes. Wired.com tested the board and gave it a mixed nod—it can go up to 12 mph, and helped their tester catch more waves, but the controller was bulky (“like a house arrest bracelet”), and the engine weighs 16 pounds (yikes!). Price: $4,500.