“Hey, I like this cartoon! Can I use it for my presentation?”

To use Mr. Obama’s words: Yes, you can.

Post them on your blog,  twitter them, mail it to co-workers, add them to your presentation, hang them on your office walls, I only ask that you mention the website address: www.whatthegregg.com.
As long as you’re not going to make money with them, go ahead.

And yes, I would love to hear what you’ve done with them!