In 1995 my middle school embarked on a project to make a solstice dial. It is much like a contemporary sun dial except instead of marking the hours it marks the solstice. The pillar has three ovals cut into it, depending on which solstice or equinox it is the sun will shine through the hole and center on a different disc. Check out the pics!

embedly http://www.flickr.com/photos/startfragment/sets/72157620101919714/