I'm a current Duke student and took multivariable calculus taught by none other than Lenny Ng a year ago. I had no idea who he really was until about halfway through, though we all knew he was brilliant. One of the nicest professors I've ever had, exceptional at explaining concepts too. He also draws pictures like a god, something that's obviously really beneficial in that sort of class. He used to say his drawings were a bit off while we would just sit there astonished. Such an amazing guy.