Does a Warforged take half damage to all attacks?
I got hit with a fireball today in my campaign and took all the damage, but I'm not sure if I was supposed to take half damage or not.
Warforged take half “damage” from Conjuration (healing) effects, that is, they are healed for half as much damage as a regular living creature would be. No other effects are halved for them. You might be thinking of the way fire and electricity damage against objects is halved (and cold damage is quartered), but objects are explicitly defined as inanimate objects with no ability scores. Creatures, even constructs, are not objects, and that rule does not apply to them. Extra doubly so with living constructs like warforged.