They have been about a while. Mythbusters have even used them a couple of times.
(, Mon 2 Feb 2009, 15:18, Reply)
and I don't watch telly, so I saw low youtube count and thought 'hmmm, shiny and new'
Still pretty cool
(, Mon 2 Feb 2009, 15:21, Reply)
"Look out, theres one guy in the middle of that large crowd with a 9mm!!"
"TURN THEM ALL TO MINCE MEAT!!!"
(, Mon 2 Feb 2009, 17:19, Reply)