The top result for "burglar alarm" on Amazon is this autodialer kit from Fortress Security. 1,200+ reviews (most of which are 4 or 5 star). I included it in our DIY alarm directory, but I confess I didn't give it much thought because it's "just" an autodialer system. But apparently it's blowing the doors off selling like hotcakes.
Have you come across this product before?