On top of unstable stairs or structures...

[rogue_noir]

This seems to be a very common dream sign for me though I've only been able to use it to trigger lucidity a couple of times. I'd find myself on a flight of stairs or on top of a structure well above the ground when the thing starts to go unstable and I'm about to fall. However, I somehow manage to pull myself together whether or not I'm lucid and have rarely awoken from such a dream though the experience itself could be pretty scary. Any idea if this is a fairly common dream sign? I'm also a little afraid of heights in real life..

[will.i.am]

If you think its what you need to help you realize that your dreaming, then yes, I guess it would be a helpful dream sign for you.

Maybe you can use this to help get over your fear of heights, after all, you are dreaming!

[redneck]

I have dreams like that all the time. Sometimes I'll be on a roof of an old rotted out house wondering If I'm gonna fall through.