i would say.. find a cockroach .. catch it... hold it and then drive red hot iron rod through its head...lol
pesticides is the best option... but if you dont wanna spend money then pick up ur foot and BAAM... hit the cockroach.....
I hate those animals. I must be happy, cause in our climate there aren't so many. Step onto them, fire 'em up, spray 'em...Just kill them.
What I find to be the quickest way to get rid of them is gasoline it's very flammable so please make sure no flames are around when using this method.