Spec Pizzas. Need I say more? The absurdity is so obvious that it is hard to understand why thoughts of spec work being positive prevail. I have never done that. And as much as these pizza guys will never visit that potential customer again I want to encourage you that you also walk away from people who show no respect for your professionality. No money, no cookies. (Or pizza, for that matter.)
By the way, we have more cartoons for you here.
Dieter Petereit is a veteran of the web with over 25 years of experience in the world of IT. As soon as Netscape became available he started to do what already at that time was called web design and has carried on ever since. Two decades ago he started writing for several online publications, some well, some lesser known. You can meet him over on Google+.