Josh and I made it our mission to find as many different signs as we could during the trip. And funny enough, as we walked back from searching for the restaurant for dinner our first night we came upon an art gallery with many of these signs inside. And they also had some interesting wall art that Josh took a video of - warning, probably not for small children to view.
The woman at the desk didn't seem hot to chat about this phenomenon but I did get enough out of her that I found out that this had originated in Florence and could be found in such cities as Valencia, Amsterdam and Barcelona to name a few. I did a little google search on the mastermind behind these unique signs who goes by the name of Clet and this is what I found: http://www.florencewithguide.com/blog/those-strange-road-signs-clet/
It also turns out that the statue that I commented on in my Firenze blog - the one that looks like a guy about to commit suicide is also his. And I apparently interpreted it incorrectly as you'll read in the link above.
Regardless, Josh and I decided that these signs were unique enough that they deserved their own blog entry! Enjoy!!