Doubtful, but it did work...
"Annabeth?" Percy said again. "You're planning something. You've got that I'm-planning-something look."
"I don't have an I'm-planning-something look."
"Yeah, you totally do. Your eyebrows knit and your lips press together and ---"
"Do you have a pen?" she asked him.
"You're kidding, right?" He brought out Riptide.
"Yes, but can you actually write with it?"
"I--I don't know," he admitted. "Never tried.

Autore: Rick Riordan