Ecobust, by Ecobust Distribution International
Demolishing concrete with a jackhammer may sound fun, but it's actually dusty, deafening, bone-jarring work. Better to drill a few holes, fill them with this stuff, and wait. An expansive chemical reaction that exerts 20,000 psi quietly cracks up the concrete.
About $50 for an 11-pound bucket of mix; ecobust.com