The Feeling of Fast

Once upon a time, I was out of shape and never ran more 10 minutes at a time. I was heaving and stompin' on the treamills at my local YMCA and it was like trying to tread through mud. Fast forward two and a half years later. I just finished a nice run on my local trail. A very satisfying run. I felt light, my legs felt like they were gliding across the ground, my breathing was steady and calm. The first 5K I ever ran was in 29ish minutes. This day I ran 10 miles in 65 minutes and some change. For the first time in my running life, I felt strong, fit, and fast.

My feeling of success, obviously, is relative. To all the people who run at a sub 17 5K level, what does it feel like moving that fast? To everyone else, where did you start out? When did you begin to feel strong? If it hasn't happened yet, when or at what pace do you think it will?

TL;DR - at what pace do you feel fast?