The architecture of retirement communities has long been traditional -- an old-fashioned look meant to feel familiar and give residents comfort. But now the generation marching toward retirement is that of baby boomers, many of whom grew up with modern design. To them, modern design is comfortable and familiar, raising the question: How long before modern replaces traditional as the style of choice in retirement living? Perhaps not that long, if concepts for a modern community called Boom come to fruition near Palm Springs. Here's a peek at some of the early designs, including this one from the firm Lot-ek, which envisioned an event center composed of stacked, slanted boxes emulating desert rock formations.