With the recent outburst of people claiming Inferno mode is too hard, and Blizzard stating it had nerfs planned to it's difficulty (see Diablo 3 Game Design Update), there are those that defy the standard and come up with this such as these:
6 Second Kill
While no video is available of this 6 second Butcher kill, maetijip claimed to have done this. He did not reveal his skill or rune build (maybe to avoid Blizzard nerfs) nor his equipment, but he did upload his stats:
Upon further inquiry, he revealed he has 128k DPS and also showed his weapon and a Youtube video (not of the kill):
He claimed most of his weapons are rare rolls and that Inferno does not need a nerf.
9 Second Kill
In another thread on the Blizzard forums a Witch Doctor was revealed to have done and filmed a 9 second Inferno Butcher kill. Here is the video:
10 Second Kill
To finish things off, in a thread on MMO-Champion we see player Maplesyrup posting about his Barbarian speed kill. He claimed 55k damage with no cooldowns and 165k damage with cooldowns. This sensible fellow also posted the build used for his kill, which he claims is only useful in this situation. The build can be found here and the video can be found below:
3 Second Kill
We saved the best for last. Athene, the guy who was the first level 60 in the game (see Diablo 3 First to Level 60), decided to blow the other Diablo 3 Inferno Butcher speed kills by doing it in 3 seconds with his eyes closed! Check it out on video from 2 angles: