Acidic Splatter( Complete Mage, p. 37)
You can channel magical energy into orbs of acid.
Ability to cast 2nd-level spells,
As long as you have an acid spell of 2nd level or higher available to cast, you can throw an orb of acid as a ranged touch attack. The attack has a range of 5 feet per level of the highest-level acid spell you have available to cast and deals 1d6 points of damage per level of that acid spell. As a secondary benefit, you gain a +1 competence bonus to your caster level when casting acid spells.