Yesterday I went to a bike show and witnessed the Wall of Death.
It's a large barrel-like wooden cylinder thing and these dudes ride motorbikes pretty fast around the walls, doing stunts like no hands and perching on the handlebars. The audience stands around the top of the barrel looking down, with the riders coming really close to the top and almost flying off and hitting the spectators.
What was cool is the bikes were made in the 1920s and have been in the same carnival family ever since. It's probably not that dangerous due to centrifugal force but it looks crazy. The riders weren't even wearing helmets and it was kind of mesmerising to watch. It would probably make a wicked music video, if the camera was looking downwards and in slo-mo.
Conclusion: 9/10 I want a go.