That is very cool! I think
moss painting on like hang up canvases might add a little life to an apartment; if one feels like doing graffiti, the sidewalk might be acceptable and legal. Also, a
living wall or
edible walls may also bring life into an urban apartment/home. Something like the
Garden Tower would provide mobile vertical growing space, and Pintrest has a great display of many possible
DIY Aquaponic systems that could be built.
Here is a picture of moss graffitti:
Here is a picture of a living wall:
Here is an image of a garden tower:
Here is a cool diy-version: