Link: http://blog.testfreaks.com/review/review-of-ipin-laser-presenter/
Quote:
"The iPin Laser Presenter is a device that plugs into the iPhone’s 3.5 mm jack to provide a red presentation laser in the tiniest of form factors. It also works with a free iOS app that allows the user to remotely control their PC or Mac along with presentation slides from their computer by using the iPhone."