Applied TaeKwon-Do DVD: Volume 2
This DVD contains applications of techniques found in patterns Joong Gun and Toi-Gye; the alternative aplications drawn from these two patterns gives access to many techniques that end up with your opponent on the floor (often painfully so for them!). You'll find upward palm block in rear foot stance used as an arm lock, U-shaped and W-shaped blocks used as throws, X-pressing block as a release from a grab - and many more alternative ideas.
This material provides a useful supplement to standard TaeKwon-Do training; why look to other martial arts to broaden your repertoire when there is so much available in the patterns which you already practice?