Fountain is a great effect that can be used in several different ways. You can make a volcano spew balls of orange lava, which fall to the ground and then bounce. Or, make a fountain out of bubbles, and have the bubbles float away on the wind. You can make a metaball fountain, in which the individual spheres merge together when they cross paths. You can choose any shape to emit from your fountain: you are limited only by your imagination (well, OK, maybe by your machine's power as well.)