When Memphians were looking at ways to enjoy and improve the riverfront, one of the top 10 suggestions was to create fun signage. "Create a riverfront-wide, site-sensitive, illustrative system of fun facts and information ... to inform and remind us, to educate and entertain our children, and to enlighten our city's visitors."
Here's a great example from Brooklyn Bridge Park of a fish sign that is both fun and educational.
Click here to read the other suggestions in the Project for Public Spaces workshop report. Page 6 gives more of your suggestions about signage.