Piper: armed with a cornucopia for shooting vegetables at her enemies (more effective than you may think) and a charmspeak that can convince anyone that these are not the droids they're looking for.
Being the daughter of a goddess of love means that Piper is well in tune with emotions, and she's accustomed to helping others work through theirs.
On that note, let's take a look at one of her shining moments: when she and Annabeth attempt to retrieve the heartbeat of the chained statue, an ingredient in the physician's cure.
The statue is held in a temple of fear, and both Piper and Annabeth are overcome with that emotion. Translation: they have the pants scared off of 'em. Annabeth, logical gal that she is, tries to think her away out of her fear…and ends up becoming paralyzed as a result. Piper counsels her, saying "You can't think your way out of your emotions" (20.26). Her advice? You just have to feel them and keep going. Because of Piper's advice, the two girls are able to team up and defeat the giant guarding the statue.
Well done, Pipes.
As they approach the Acropolis, our heroes are accosted by a race of snake people who prove surprisingly susceptible to Piper's charmspeak. It's like she speaks parseltongue or something, leading all the snakes away like she's the…uh…Pied Piper…and they're her rats.
But no matter how powerful her charmspeak is, Piper can't stop Leo from sacrificing himself to defeat Gaea. She mourns the loss of a friend, and that means it's time for someone else to help Piper with her emotions. Jason comforts Piper by telling her, "We have to believe in Leo. There is no way he would die so easily" (57.64).
Moral of the story? No woman is an island.