Give a presentation wirelessly from your iPhone or iPod Touch without additional presentation software!
Air Projector projects PDF documents and photos wirelessly from your iPhone or iPod Touch to a web browser connected on the same local network. No additional client software is required.
Always be ready with your key presentations in your pocket.
Via Ana Cristina Pratas, José Cuerva
It'll only show a bunch of images for me (can't see how to show a PDF) so presentations have to be turned into a series of images and then into a album.
I've not tried it in class yet but, in theory, I could present to every screen in the room, they all have laptops, and that's awesome!