There has been a category for Zippy the Pinhead and the locations that he visits in the real world at Waymarking.com.
The Zippy the Pinhead Locations category was not an original idea. The idea stemmed from an locationless cache at Geocaching.com. Locationless caching was stopped the 1st of January 2006 on the geocache site and waymarking was started later that year. Many of the archived locationless caches were moved to the waymarking site but sadly the Zippy locations cache was not one of them.
Below is the original idea by geocacher Gator Man;
Zippy's Roadside Attractions (you must have a free geocaching account to view this listing)
A partial history of this category and its start can be found in the waymarking forums here and here.
After some time past I decided to explore the possibility of creating a new waymarking category for the Zippy the Pinhead strip.
Subsequint posts will detail locations by state and country to assist in research for the category submissions.