[KatjaS]

Yes, even that I've seen on TV, but I think German curlers are not that good, so it's not that popular (good sports = sports where Germans win). Sledding in all its ridiculous forms is on TV regularly in the winter for example.

[kadiHH]

Sledding is one of those sports that's fun to do, but not so interesting to watch others do. I went bobsledding for the first time last year up at Whistler, BC where the 2010 Winter Olympics were held. It was a great rush, but we just had two runs, so it was over fairly quickly. I went ziplining for the first time as well--I think that's becoming more popular in the Alps?

[KatjaS]

Sledding is mostly watching slightly overweight people in way too tight clothing skid down an ice canal while staring at a clock.

As for ziplining, someone else has to answer that, I'm more of a beach person than a mountain person, so I wouldn't know.