Ambidexterity (idea)

In Dungeons & Dragons' third edition Player's Handbook, Ambidexterity is described as a feat (special ability) that your player character (or "PC") can acquire. From the Player's Handbook (p.80):

"You are equally adept at using either hand.

• Prerequisite: Dex 15+.
• Benefit: You ignore all penalties for using an off hand. You are neither left-handed or right-handed.
• Normal: Without this feat, a character who uses his or her off hand suffers a —4 penalty to attack rolls, ability checks, and skill checks. For example, a right-handed character wielding a weapon with her left hand suffers a —4 penalty to attack rolls with that weapon.
• Special: This feat helps offset the penalty for fighting with two weapons. See the Two-Weapon Fighting feat, page 86, and Table 8-2: Two-Weapon Fighting Penalties, page 125.
  A ranger wearing light armor or no armor can fight with two weapons as if he had the feats Ambidexterity and Two-Weapon Fighting."

A great feat if you have plenty to spare, in this noder's opinion. It helps reduce penalties for being a badass and fighting with two weapons, which, obviously, is for hardcore ass-kickers. Similarly, it helps the user use double weapons.