I've started using green screen to help get more variety in the kinds of hazards people could be dangling over. I can think of glue, spikes, lava, and with green screen I can add chasms and sinkholes to the list. I just need to learn how to use green screen more cleverly to make it look as believable as possible.
I'm aware that glue vids tend to be more popular than cliffhanging ones, though I admit that crossing rickety bridge scenes are my fave to film as well as edit. That might mean more glue vids coming in the future, but we'll see ;)