Hi, I came across your posting while trying to get more information on a new driveway surface called SCR, Shredded Composite Roofing. Apparently it is ground up old asphalt roofing that is applied approx. 2" thick. The cost is comparable to gravel ($6.00/yd) There doesn't appear to be much information about it, but I have a contractor coming over tomorrow to give us a quote. I'd be interested in any other alternatives that you might come across.