Note: SmartMedic no longer works as of WoW 2.0.
SmartMedic takes the hassle out of your health and mana management--no more guessing which bandage, health potion, mana potion, food or water you should use. SM will automatically find all health/mana items in your inventory and use the one most appropriate for your requirements (or your target's, in case of bandages).
Please find it here.