I search for solutions in this order: Past Code, Unreal Source, Wiki, BUF, groups.yahoo, google, screaming at monitor. – RegularX

From Unreal Wiki, The Unreal Engine Documentation Site

A SmokeGenerator does exactly as it's name suggests. It creates smoke. ;)
Using them is very easy. You just need to place the SmokeGenerator where you want the smoke to go, adjust the settings and you're good to go. You do will have to trigger the SmokeGenerator before it will start emitting smoke.

Properties

float SmokeDelay 

The delay between two puffs (smoke).

float SizeVariance 

How much variance in size the puffs (smoke) may have.

float BasePuffSize 

How big the base size is of the puffs (smoke).

int TotalNumPuffs 

How many puffs does it have to emit, before it stops.

float RisingVelocity 

How fast do the puffs go up.

class<Effects (UT)> GenerationType 

 ??

bool bRepeating 

Can be retriggered after the amount of smoke specified in TotalNumPuffs was generated.