Vesper Primer+Standard Actions+Bardic Performance+Inspire Competence (Su)

A bard of 3rd level or higher can use his performance to help an ally succeed at a task. The ally must be within 30 feet and able to see and hear the bard. The ally gets a +2 competence bonus on skill checks with a particular skill as long as she continues to hear the bard's performance. This bonus increases by +1 for every four levels the bard has attained beyond 3rd (+3 at 7th, +4 at 11th, +5 at 15th, and +6 at 19th).

Certain uses if this ability are infeasible, such as Stealth, and may be disallowed at the GM's discretion. A bard can't inspire competence in himself. Inspire competence relies on audible components.