BASE Jumping: is very extreme activity that includes a parachute (can be used both parachute and wingsuit) to jump from fixed objects, with unopened parachute like skydiving. The acronym “B.A.S.E.” stands for: Building, Antenna, Span, Earth – four categories of objects from which B.A.S.E. jumper can jump.
Extreme canoeing (a.k.a whitewater canoeing or whitewater racing). These extreme guys race specialised canoes and kayaks down a dangerous whitewater rivers. There is also such a class like Extreme Canoe racing, that includes much more complicated rapids, leave it for real pros 🙂