I saw a file for purchase on videohive.net (videohive.net/item/sketch/91631) that gives a sketched look to footage, and I thought to myself, I could do that!
Here's a video as an example:
"Scribbles" effect in After Effects, turn an footage into a sketch style animation! from Michael Lansdell on Vimeo.
It's a bit blocky from the compression in the example above, still, if you'd like to use this for your own footage, you can download the project here. Just drop your footage into the "source" timeline, and you're done!
One other thing you'll need is a paper texture of your own, these are easy to make (just scan some paper!), or to find online if you'd like something a bit more exciting :o), just plonk it underneath the other comps and that's it!
If you find this useful I'd love to see what you've done with it, so please let me know.