Life Regen on all possible pieces at max possible roll: 3956 (not including set/legendary affixes/mods)
1H LoH ilevel63: 959
Up to 6% Steal Health Percent (3% on Weapon, 3% on a might barb belt with your main stat)
With enough vitality, armor, and vitality you would perhaps be unkillable no matter what class you are. And this doesn't even take into account passives, abilities, runes, and followers!
I am guessing someone has a build with these kind of stats on a ranged class that does good damage! I envy thee :D
EDIT: Aparently Life Regen can go up to 5217 which I did not know (http://www.diabloprogress.com/hero/leftylouis-2528/Okeuh/15849778).
And Aparently Life on Hit can go up to 5847