A question for plant-lovers

Real quick question here.

I am looking to grow a plant that needs really minimal space/resources! Eggshell minimal, in fact, 'cuz it looks too cute not to at least try it.

Basically, I just want something I won't have to re-pot later. Unless eggshells would biodegrade quickly enough or crushing them wouldn't horribly kill the plant or something. I would also prefer a plant that is more vertical than horizontal/has a stem and leaves (no moss, lichens, etc).

Any suggestions?