It's not "extreme" by any means but we've got a technique for fishing the canal I call "guerrilla jigging". Long distance - long drifting big jigs in a fast current in deep water.
Whack a 30+#er with 150+ yrds of braid out while standing in one precarious spot and you've got a rumble on your hands.
It can be extreme if you want it to be. Boat Fishing can be very extreme. As for surf fishing its only extreme if your deep wading or skishing. Some of the places we wade are very extreme.