I have made a yogurt-like substance from coconut milk. I scalded coconut milk (from a can, so this sterilizing step probably wasn't necessary), than added whey I collected from yogurt. I left the mixture in an insulated cooler to keep it warm overnight. It eventually setup to a consistency similar to yogurt, but there was much more clear liquid at the top than one would expect (lots of "whey", I suppose?). It tasted like yogurt, and wasn't unpleasant, but wasn't a clear win in my mind. Several further attempts resulted in mixtures with even more "whey" and less yogurt flavor. I'm sure the temperature and many other important variables were drastically different between my batches. I'd recommend just trying, and seeing if you can make it work. Post an Instructable when you do! Maybe add sugar so the bacteria have more to eat? Finally, if you want the yogurt to be vegan, use some uncooked sauerkraut juice -- it is the same bacteria.