I can still remember them vividly. I was trying to hit a flat first serve from the ace court to my opponent's backhand side (both righthanded). The serve would land very short brushing the line at normal speed. Each and every time my opponent(s) would just stare at the ball and couldn't even react. I think I did it less than 10 times during my 3yrs of tennis playing. To me that's what tennis is all about. At my level if I could do that more consistently (maybe 1 out of every ten trials) I could probably own the game. Is there anyway to do it consistently? It doesn't have to brush the line, landing short to the opponent's backhand at an acute angle is the key. For me, they only come by accident.