I see a lot of people rag on awareness and while I admit it isn't really the greatest mitigation cooldown, I use it as a mitigation utility on drk. It's hard to observe results with it due to the way the damage is taken in this game but I think it's effective if you have synergy with another cooldownif the enemy can crit.
Combined with dark dance or foresight usually. On war I heard it could negate the rear crit but I don't know if they changed it.

Not something I use all the time but I pop it with other cooldowns usually.