Another prototype from Promise Design, Phytoslim is a modular system for growing plants on walls. Its slim panels are made of coconut fibers and supported by a hidden plastic skeleton. The 2"-thick pieces supposedly attach to any surface, indoor or out, vertical or horizontal. Although we're absolutely smitten with the idea of a grass-covered interior wall, the sheer logistics leave doubts in our minds: Watering? Trimming? Bugs? We'll wait patiently for the experts work all the kinks out of a development that could lend creative new meaning to the term "landscape architecture."