Having attended and enjoyed the last 3  Ingenuity Fests, I encourage all to buy a full week end ticket and make a career out of the fun.   Here's the link to the Ingenuity web site. 

All the vacant buildings in downtown Cleveland provide cool backdrops for the fest.  The composite side walk chalk image above is "High Dive", a 2006 Ingenuity Fest look under the concrete floors of one vacant building by Barbara Chira, Jesse Rhinehart and Jan Stickney.  

Watch out!  Don't fall in..