We have one of these and someone put a piece of a popsicle stick and wrote "Rock Concert" - Love Rock Art.Garden Trinkets - Awesome Ideas, Projects and Tutorials! Including, from 'instructables', this creative 'garden thing' project with rocks.
Craft with the kids this summer DIY garden stones - use a cake pan! Also, using clear contact paper to hold the mosiac pieces in place while the concrete sets is also kind of brilliant. I want to use mirror pieces, red gems, and black cement dye.