Me no cat lover, but I still find it funny and it seems it's the winner today :)

And I love the idea of bringing this sort of poster, or something similar, to this community

Basically any sign that passes on a funny message is good, in my opinion. We used to have a very good photographer from Eastern Europe, hunting these signs and he had so many good ones. I always said I'm going to try to collect some, but it's not so easy, depending on the country, of course.