Many individuals today, such as many a UFC fan, may not realize that much of the ground tactics employed in the ring are derivatives of the Japanese system to begin with. These pictures are all from Judo (judo is a sport derived from Japanese jiu-jitsu, as is the grappling art of Brazil).
Realistically, Judo has a very solid ground component, despite being known by for its throws and leg sweeps. I remember learning a scarf hold when i was about eight-years-old. I've never forgotten it, and never stopped believing its effectiveness in controlling an opponent (more damaging joint manipulation or chokes can be added to the basic technique if required). I also picked up a couple of standard defenses from high school wrestling classes that stay with me to this day.