I have been to a presentation where someone put in an animation of letter dropping and forming a line.
How do I do this?

Hi Emilie,

Thank your for your post;
This has probably been accomplished by using a 'Typewriter' style of animation option, try these steps,
Type your text in your placeholder, Go to menu command Slide Show; Select Custom Animation, from the side bar that appears choose Add Effect and Fly In from what ever direction you require: then click the little drop down arrow to open the Fly In dialog and from Effect tab choose the Animate text By Letter option, click OK and it will animate when you are in Slide Show view, "Not so magic after all!"
I hope that helped, regards Pete