On June 30, 1859, a French acrobat added something new to the already-dangerous trend of performing crazy stunts at Niagara Falls: he crossed its gorge on a tightrope. We'll get to him in a minute, but first, a few other people decided to seek their fame by risking their lives at the Falls (and one who didn't mean to).
5. Captain Matthew Webb was the first person to ever successfully swim the English Channel without any help from artificial means. You would think that would mean he would have somewhat of an advantage when it came to swimming through the Whirlpool Rapids below Niagara Falls, but sadly, that wasn't the case. Reports say it looked like he survived the first half of the swim but may have met his match when he tried to cross into the entrance to the whirlpool.
7. Steve Trotter followed in Soucek's footsteps the next year. He, also illegally, went over the Falls in two pickle barrels attached end-to-end. They were insulated with the same foam used to pack nuclear warheads and Trotter was equipped with a lifejacket, flashlights, oxygen tanks and a two-way radio. Unlike Annie Taylor, Trotter loved his ride, telling people that it was "like the best roller coaster ride you ever had as a 10-year-old." Being a 10-year-old probably wasn't too distant of a memory for him - at 22, he was the youngest person to ever go over the Falls in a barrel. He went over again 10 years later, this time joined by fellow daredevil Lori Martin. Trotter didn't get permission for that stunt either, nor his "Tarzan" stunts off of the Golden Gate and Sunshine Skyway Bridges.
The first Tarzan stunt occurred the same year as his first Niagara stunt - he jumped off of the Golden Gate Bridge while attached to a cable with a wooden disk at the end of it. He stood on the wooden disk and swung back and forth before he was caught and arrested. The Sunshine Skyway incident happened in 1997 and didn't go as smoothly: Trotter and five others attempted the same stunt but didn't test the weight; the cable snapped and at least two of the other jumpers were severely injured.
8. and 9. Peter DeBernardi and Jeffrey James Petkovich were the first people to do a two-person "jump." They went over the Falls in a barrel equipped with rudders to help them steer through the rapids and a video camera to record the entire event. DeBernardi apparently wanted to discourage people from getting addicted to drugs like he was and especially wanted to set a good example for his then-two-year-old son. How going over Niagara Falls in a barrel was going to do that, I'm not sure... anyway, both of the men in the barrel survived. No word on if his son ever became a drug addict or not.