Marcy,

I had to laugh when I read this. My mom used to do the same thing, but with a bit of a twist. First, she started by taking pictures to show her neighbor. The response she received was similar to what you did - "let Ben know and he can come and clean it up." That worked for less than a week, then Ben was nowhere to be found... so, every morning she would go out in the front yard, scoop up the poo, and then place it strategically between their front door and their car door. It took about 2 weeks for them to get the hint.