Many people hide the TV in a bulky armoire, but architect James Wagman found a sleeker solution while remodeling a prewar New York apartment: a built-in cupboard that, decked out in traditional molding, looks like an original feature. Most people want to be able to put the TV away, Mr. Wagman said, including his client, a TV casting director. The cupboard opens to reveal media storage and a flat-screen that slides out and pivots into viewing position.