I can't think of a good name for this one sorry. This is very similar to a bottle cap salute.
Have you ever kept all of the stands that the fountains come on. If so this is something you can do with them.
Materials:
2 fountain stands ( take the stands off the fountains (i.e. whistling petes) and cut around the cap of it. Do this twice. So now you should have two caps.
Explosive comp.
Plastic cement is optional
Tape is a must
Fuse you can decide the length
Step 1: Fill the cap to the top with explosive and the second cap half way.
Step 2: Now connect them with spilling as little powder as you can.
Step 3: Poke a small hole at the top
Step 4: And tape it up real good.
Step 5: light and get away.
Effects: These are good to destroy pop cans with. You could always use bigger caps from other fountains.