I made an automatic scenario builder based on "A Dirty World"s 10 d10 roll system and... it was kinda boring. Unless you roll 4 or 5 of the same number you don't get any juicy crimes happening and you're stuck with things like "Negligence led to some widespread, low-grade problem - mild illness, a horrible odor from a sewer, car breakdowns, etcetera. Nothing life-threatening." ...Drama!
So I found a pulp plot generator on Drive Thru RPG for cheap. Swung that into action and it's way more fun but a lot less believable. Eg:
A mad scientist wants to hunt for a man in the city slums. The story starts with the players getting into a fight. The players encounter a dense professional fanatic, an impulsive native soldier and a weak evil scientist. The story twists on a greater villain!
Obviously you have to fill in the blanks but it's fun spinning the numbers and trying to invent something cohesive from what they give you.