In SR, the closest thing I've done is that several of the smokers needed to burn one after particularly pitched and brutal fights.
In Marvel Superheros, that's a different story. In a nutshell: players in the Age of Apocalypse setting are escorting a bunch of human refugees to a safe zone. They hear that some have been seperated from the group and go to find them. They find this little girl, torn clothes, face smudged, holding a ragged teddy bear. Of course they try and be nice so she will come with, only to hear "Teddy dosen't like you". Teddy then grows to about ten feet tall, grows claws that would make Wolverine pause, and fangs to match and get CREAMED. Nothing they can do will hurt this thing (the flame user lights it up, so then its a flaming teddy bear) and they literally blew the stuffing out of it before they realize its a mental construct and the telepath zapps the girl. Now, fast forward about six months, the timeline has returned to "normal". Same players, see same girl, give chase...into a dark warehouse. Lights come on revealing rows...and rows...and ROWS of teddy bears with a voice echoing "Teddy dosen't like you".
Two players paled, one choked on his Dew, and I was called everything but a white male by the group.