If against the wall can work-I once hung a pair of McIntosh XR 14s (typically floor standing at 50-60 lbs each) by through bolting a piece of heavy chain across the speaker backs and then hanging the chain over a lag screw with a washer driven into a stud. Sort of like hanging a picture, only very heavy duty. I needed to pull the woofers to gain access to the inside of the back of the cabinet to tighten the carriage bolts anchoring the chain. I still have the speakers and haven't bothered to remove the chain.
