Object following dynamic text (pen/pencil)?

Are there any good tutorials on how I might create something like the following?

I’d like the user to input text. Either while they are doing it, or once they are finished with a form and hits submit, a pen/pencil actually writes out the message rather than just the text appearing. I’d like the object/pen/pencil to follow the text and show like it’s writing it out.

Is that possible? Where would I start with that kind of thing?