GTA-IV Forklift Easteregg (or Something like that)
Here is what happened:
I was hanging out in liberty city and killing some polices, so I decided to drive a forklift, so I spawned one and drove it. It was fun but suddenly a bullet from polices hitted that gas tank in back of the forklift and I saw flame comes out of it just like the picture below. I got of it and I shot the various places of the gas tank and saw it again. It's very funny, I recommend you to test this glitch (or whatever it is)!!!!