I'll just mention that the exalted familiar options from BoED can also be pretty handy. The lantern archon will provide you with constant:
Magic Circle against Evil (Su): A magic circle against evil effect always surrounds an archon (caster level equals the archon’s Hit Dice). (The defensive benefits from the circle are not included in an archon’s statistics block.)
So you get +2 AC & Saves vs. evil, not to mention constant mental protection, so long as your little buddy is nearby. Sure it costs a feat, but still pretty darn handy.