With the Greatest Living Hitter thread going on, this seems like a natural topic. I'm surprised no one has started it yet.
Who is the best pitcher still living today? I'm sure I'll forget some candidates, but a few from the top off my head include:
Eckersley (do relievers count? His stint as a closer was awfully good and he had at least a decent career starting as well.)
Koufax was the one I thought of first, but I guess longevity is the question with him. (Actually Warren Spahn was my 2nd thought, but I believe he has passed away.)