Wow. I just had the most fun I've ever had GMing a trad game. All I had was two plot points (PCs are going to head to a railyard, PCs are going to take a train), that we had discussed beforehand. Everything else flowed from prompts that this NPC generator gave me. The PCs interacting with the NPCs made the plot. I just re-incorporated and said "yes" whenever the players asked a leading question ("Does he look like someone I've seen before?"). Turned out one of my random NPCs burned down like a sixth of Denver after releasing a malevolent spirit from a mysterious crystal. So fun.
Check it out!http://members.iinet.net.au/~rene1/realnpc.htm