Honestly I could get really interested in soil.

So complex, so important to Earth.

History, future, science, nanotechnology, geo-engineering, soil could do lots of things. Central to terraforming and extension of DNA timeline beyond the death of Sol.

Super soil could be the self replicating self correcting, durable system that stabilises life on Earth. It can also store massive amounts of information in DNA.

Self governing systems are always interesting to me.