Metal storm.
Been following this style of weapon for a while now.
This is a small one, but they also do ones with 40mm rounds.
Rounds are stacked behind each other in tubes (barrels) and can be electronically fired via the rim of the round, so you can fire them all at once, or in patterns whatever you like.
This would be devastating.
Goalkeeper
meh, stuff that, i want me one of these
-james