Even more than that. Check out the iSpindel[1]. Basically build your own tilting hydrometer. Now I have electronics in the mix too.

I have also become fascinated with yeasts (biology!) and really want to start harvesting and propogating my own from local varieties.

Hops is another complex subject. So many different varieties with different aromas and flavours.

[1] http://www.ispindel.de