well, lots of things awe me. Size is an easy way to awe people, though it generally has to be REALLY big for that. One of the wonders of the world-big, in my opinion. But even more so, I think something that is really well-done. Like a very intricate piece of jewelry, or a complex piece of machinery. Or nature. Nature often awes me.
I think for me, it comes down to a - "I don't think I could do that myself, so it's amazing that this other person can do it" sort of thing.