(Spoiler warning for those who have not finished the game.)
The Build: (Non Boss) http://us.battle.net/d3/en/calculator/barbarian#WePikR!ZYd!cYbYcY
After battling with the final boss of inferno act 4 for over 1 hour, I finally managed to take him down:
I tried for like 12 hours in total to kill the final boss, dying over and over again to those black things on the floor which 1 hit kills you.
I have done everything solo, unless you count the auction house. I can easly take down mobs/elites on act 2, I can also kill most of them on act 3 and 4 aswell, however there are some nasty combinations which take a lot of work.
Ignore pain + life leech works well.
So to all those who think Barbarian isn't usefull in Inferno act2+, hang in there, it was amazing to finally find a build which worked.
Stats Screenshot:
