Haha! I love that Extreme Ironing!
As I used to talk about constantly - I did Muay Thai and trail running for 2 years and was injured all the time, but I think it could have been avoided if I wasn't overtraining.
Here's my list:
More Dangerous:Boxing (only sports-related question on Canadian life insurance applications)
Luge
Rock Climbing
Rugby
Free Diving (that's without scuba gear...

)
Surfing
Downhill Skiing/Snowboarding
More Safe:Golf
Swimming (low impact exercise, high supervision rate, easy access to help)
Walking/Hiking in populated areas
Weight lifting (technical, precise, calculated, controlled environment)
Volleyball
Badminton
Tennis