Tim Lincecum is a 5' 10" 172-pound Major League pitcher with a 98-mph fastball. Such velocity out of such a small frame is attributed to his unique (but mechanically sound) pitching technique.
One key to Lincecum's delivery is to keep his left side, especially his left shoulder, aimed toward his target for as long as possible. "Don't open up too soon because then you lose leverage," Tim says. "If you twist a rubber band against itself, the recoil is bigger. The more torque I can come up with, the better."
Where Lincecum truly separates himself from most pitchers is the length of his stride. It is ridiculously long as it relates to his height. And just as his left foot, the landing foot, appears to be nearing the ground at the end of his stride, he lifts it as if stepping over a banana peel -- extending his stride even more. The normal stride length for a pitcher is 77% to 87% of his height. Lincecum's stride is 129%, or roughly 7 1/2 feet.
As a casual fan, it's difficult to see what's so different and violent about Lincecum's pitching technique.