The 10 Misconceptions article linked in a previous post was written by Norman Varney, who owns AV RoomService, Ltd., that sells a variety of vibration control products based on decoupling speakers and equipment. No great surprise Mr. Varney doesn’t support spiking speakers to the floor. Here, and here are a couple of other articles written by Mr. Varney.
Their Equipment Vibration Protectors (EVPs) are isolation feet that "de-couple vibration transmission by converting the mechanical energy into thermal energy." These appear to be basically Owens Corning 700 series fiberglass with either rubber or felt covering the top and bottom. The Owens Corning board is an effective acoustic insulation. I suspect the softer version could make an interesting DIY constrained layer equipment platform project. Their RoomDamp2 also looks interesting.