Hartwood

When a tree falls, its lifeforce slowly retreats into the core wood and fades out of existence. If it falls in the feywild, there is a chance that its lifeforce is sustained by the latent magic of the plane. In such a case, the dead outer layers eventually decay to reveal a column of still living Hartwood at its core. Guided by the soul of its parent tree, Hartwood has a penchant for helping its owner push past mortal limits and accomplish legendary feats when the need is greatest.
  Description: Hartwood is an impossibly pale, almost luminous material. Sturdy yet compliant, soft yet unyielding, it practically embodies the platonic ideal of workable wood.
  Natural Properties: Hartwood counts as a fey entity for the purposes of spells and effects that refer to a creature's type, such as the spell Detect Evil and Good. When a creature attempts to use an item made of Hartwood to accomplish an extraordinary feat, such as make an impossible shot, survive an impossibly powerful blow, or pick an impossibly difficult lock, the item may choose to have the creature roll a 20 on the skill check, attack roll, or saving throw. This effect can't occur more than once a week. (The decision to activate this property is controlled by the DM. It generally triggers in moments of narrative climax.)
  Example Item: Hartwood Quill. Some of the world's greatest poems and stories have been written in a moment of inspiration granted by a Hartwood quill.