Everybody lines up a certain distance from a single basket... say 30'. You space people out in a circle around it. On the count of three everyone putts AT THE SAME TIME. Everyone who made it stays in, everyone else is out. Then you do it again with the people that made it. And again as often as needed until you have the number of winners you wanted. They get whatever prizes you lined up. I think they can be fun...especially at large events. The effect is what is thrilling about it.
You're not going to find a better explanation than this. They are a lot of fun, but you do need to have someone to govern the throwers. I played a tourney a while back that had a great lot of prizes for ring of fire and one guy kept throwing his putts late and winning prizes. It pissed me off.
That is a good idea. I'd wondered how you kept people from doing this in events where you've got over a hundred people in the ring. It could be chaos... I mean, that's what's fun about it, but you don't want cheaters.