A client sent me an email, claiming he had attached a pair of images he wanted to use for an 11"x17" poster.
However, the attachment was a single 800 pixel wide compressed jpeg.
I downloaded the jpeg, and it was a giant white canvas, with the two smaller images he wanted me to use on it. I cut them out to attempt to use them. They were only 300 pixels wide. And made out of jpeg noise.
Worth noting was that the poster would be advertising a digital art gallery showing.