Opaque glass closets can be made with several options, including bubble glass, rain glass and other textured patterns (pictured is frosted glass).  Glass is typically 3/8" to 1/2" thick in a frameless design with polished or brushed nickel hinges and handles.  Other finishes also available to match a client's home décor.  Another popular design option is the use of switch-light glass in which glass that is transparent becomes opaque with the flick of a switch.  Same design concept could be applied to other rooms in the home  -- exercise rooms, wine rooms, water closets, etc.