It would be cool to encase aliens without contaminating the water somehow. Fiberglass water storage tube tanks for passive solar heating & cooling system Trombe walls. Prevent temperature swings in greenhouse or sunroom by storing excess solar energy.
I absolutely love this. Reminds me of an adobe bubble house I saw in an article many years ago. Richard Olsen's Book Handmade Houses Showcases Beautiful and Unusual Homes : Architectural Digest. Probably for my future little house in Europe.