Winblok is a South African construction innovation by inventor Al Stratford, former president of the South African Institute of Architects. Intended to be used in buildings constructed with masonry, it's essentially a modular, pre-cast concrete window frame that negates the need for sills, reveals and the like; you just brick right up against it (and over it) and you're done. A reveal on one edge is fitted for a window, and the architect specs out which way the Winbloks face, providing options for having the window flush with the inside wall or the outside wall. A variety of different window styles are designed to fit within the system, as well as louvres and burglar bars.
Winbloks are made in different heights for reasons of passive solar management. By cross-referencing the latitude of the building site, the architect can choose the appropriately-sized Winblok to create a "solar cut-off angle," blocking direct sunlight while allowing in the ambient light. This is to lower cooling costs and obviate the need for additional shades and overhangs.
I'm not sure why these haven't gained much traction outside of South Africa; any practicing architects want to chime in? While it's designed for masonry construction and not, say, the dimension lumber platform-frame construction prevalent in much of the U.S., there's plenty of places that use masonry construction in the American Southwest, so I'd imagine I'd have heard of this system before. Because it definitely isn't new—Stratford used it to build his own house shortly after prototyping it, and that was back in 1980. Winblok hit the marketplace in 1985, and today Stratford's company, Wintec Innovation, is still a successful venture.