In the Brawn skill tree from Salvador (Gunzerker) there is a skill called "Come At Me Bro" that has the following description:
Action Skill Augment. While Gunzerking, taunt your enemies and instantly gain Full Health. Taunted enemies are more likely to attack you, but for the next few seconds you gain massive damage reduction. NEXT LEVEL: "Nigh Invulnerability is a hell of a drug."
Now I am interested how high the damage reduction is (though the red text says "Nigh Invulnerability" I assume that it will be very high) and how long it does stay active.