Have you ever seen a more casual off-the-backboard dunk? He's just in transition and then realizes "Oh yeah, I can do whatever I want, I'm LeBron James" -- and that's exactly what LeBron James does:
LeBron James throws alley-oop off backboard to himself
This is so very LeBron. He's apparently quite bored with basketball's current level of difficulty, so he brings it up a notch. Check out this sick dunk.