Tom Cruise once “completely knocked” out his co-star Rob Lowe while making a movie in the early days of their careers. There are lessons to be learned when watching Tom Cruise hard at work. The most obvious would be how brilliant of an actor he is, and just how fearless a stuntman. But the most valuable? It would have to be this: you seriously don’t want to mess with the guy. The 62-year-old American actor is a Hollywood legend, and he’s been playing tough guy Ethan Hunt in the Mission: Impossible movies since 1996. He’s only grown more and more daring as his career has evolved, yet Tom has al…