I'm playing an Undead bloodline Sorcerer (currently 4th) and that DR 5/- vs nonlethal is tempting me into some sort of cheese. So, does anyone know of any way(s) to convert damage I take to nonlethal, or other useful tricks I might try? I suppose I could always save up for a Dancing Merciful Vicious melee weapon.
Yep the Spell is called Ablative barrier
It converts the first 5 point of damage from any source into non-lethal damage for a total of (level x 5HP) from memory, it can trigger multiple times per round.
It's also nice for healing because you heal 1HP of non-lethal for every healed point of lethal damage so you heal twice as fast after or during combat.