If guess if you're a musician of any kind, getting to perform with The Rolling Stones would be a dream come true. Maybe a little flipping out would be involved? Maybe a little "let me sit down and process this" might come into play?

Well, I didn't see any of that on this video. But that doesn't mean that Taylor Swift didn't take some private time somewhere to flip out, to sit down, to process.

What I did see, and what you're about to see, is Taylor with Mick Jagger and company singing one of my favorite Stones songs, "As Tears Go By."

Check it out: