The poison ring (Dragon Compendium, p. 111/115) is an amazingly powerful weapon in the right hands. Not only is almost every class proficient with it, but it has special rules that can make normally tough enemies incredibly simple to defeat. Dragon? Not a problem, just be sure to let the rogue dual-wielding poison rings get his flank on, then sneak attack it into the grave. Golem? A fighter with a poison ring will be able to land virtually every blow, adding his strength, feats, and weapon enchantments to the damage and take it down quickly.
Advantages:
- Simple weapon.
- Light weapon, for dual-wielding a pair or Weapon Finesse.
- All attacks are melee touch attacks!
- Poison friendly.
- Disguised, so it is very hard to detect as a threat.
- Can deal damage subtly.
- Worn, so it is always in-hand for things like Warning enchantments, and though the rules do not state it, a poison ring should be as hard to disarm as spiked gauntlets.
- You still get to add to damage (Sneak Attack, Weapon Specialization, weapon enchantments, Strength, etc).
Disadvantages:
- Not Power Attack friendly.
- Always does only 1 base damage, regardless of size.
I'm honestly surprised there isn't a handbook on this site detailing every possible way to maximize this weapon. It should be placed right up there with the crescent knife, rope dart, minotaur greathammer, and other weapons that nearly every character should consider taking.