I Have Sinned!
And I repent. Despite being a totally cool, suave, and debonair blogger it turns out I've been guilty of a newbie sin--hotlinking pics with abandon--for quite some time now. I've just become aware of this yesterday, read up on it, and I plan to go back through my archive and correct the problem.
For shame, and thank you to the commenter who alerted me to the problem. It won't happen again.