Pressure points and pressure point strikes are great IF used in the proper context. In law enforcement, pressure points are used on non-compliant but un-aggressive people. An example would be a person laying on the ground with his hands clenched under him. This guy just doesn't want to be arrested, he is not trying to escape or to harm you. This person may submit after applying "touch pressure" pressure point stimulation. There are several pressure point strikes that I have also found effective, but they require practice to be able to strike a combative subject. Pressure point strikes that I have found effective are, striking the brachial plexus origin, brachial plexus tie-in, radial nerve, common peroneal nerve and the femoral nerve. In ref. to DavidCC's post it sounds to me like you were on the recieving end of a strike to the brachial plexus origin. Striking this area will not render you unconcious but it will drop you and cause a "stun" effect for upwards of 1 minute.
Pax
Cujo