A toy building block of a type which may be interconnected with similarly configured blocks has a hollow box-shaped structure having a top with cylindrical stud coupling members, and sides which together with the top define a downwardly opening cavity into which the cylindrical studs of a like configured block may be inserted for frictional interconnection. One or more integrated circuit chips are embedded within the molding material of the block, and leads incorporated within the block studs and sides provide electrical interconnection between blocks when like configured blocks are brought into frictional interengagement. In a described embodiment, components of a digital video recording system are apportioned to different blocks which when interconnected provide the complete system functionality.