Three notable generals who successfully implemented this strategy are Tariq ibn-Ziyad, Hurnan Cortez, and Xiang Yu. They managed to take on armies many times their size by deliberately cutting off any channels of exit.

Read more about them here:

http://en.wikipedia.org/wiki/Tariq_ibn-Ziyad

http://en.wikipedia.org/wiki/Hernan_Cortez

http://en.wikipedia.org/wiki/Xiang_Yu