The SolidDrive is a powerful patent-pending sound transducer that transmits acoustical energy through almost any solid surface. So why have speakers when you can turn your coffee table into a sound resonating piece of your home audio setup. Said to deliver high-quality sound with the frequency response of conventional diaphragm speakers, the SD1 works with most rigid surfaces including glass, drywall, granite, metal, wood, ceramics, and composites. Cool but pricey at $500-$550 per channel plus installation. So you must really hate the sight of speakers to go for this one.