The reasoning of the researchers, from Iowa State University, went like this: Greenhouses are really large. Micro-fluidic devices used to grow plants and test unique growing conditions are really expensive. So, what about Legos? Transparent blocks of the common toy are perfect for creating the micro-environments needed to study plants and their roots, the researchers wrote in the journal PLOS ONE--they are cheap, abundant, easy to re-arrange, and can be tailor-made with CAD software. The Legos can even be sterilized in an autoclave (basically like a small oven for sanitizing lab equipment) without melting, while remaining translucent.