Knock-off speakers. Typically sold out of a van or suv by shady salesmen with a story along the lines of "These are high end speakers and we have extra units we need to sell or our boss will be angry, so we will give you an amazing deal". They might show you a catalog with MSRPs of $2000 or more and tell you they can sell them to you for $200-$300. They also show up on Pawn/hock shops and on Ebay (ebay is a front, typically the people that list them are the ones that bid them out).
Theater Research is one of the safer of the scam speakers as they typically don't pose any harm to your existing equipment. But some other scam speakers companies sell speakers that can potentially damage your equipment.
I would advise you to stay far far away from these speaker systems. Christmas season brings these scammers out of the woodwork like no other, report them if you can.