There's a whole series of these on Newgrounds, each one longer and more complex than the last. But Xiao Xiao is more my speed as far as Flash-animated mass-murders go.
I liked how the guy in the top right danced the whole time, up until He got shot in the face, I guess.
I kinda thought if he let well enough alone, then it would have rounded out the ending better.
Still, Xiao Xiao is quite the chaotic fun