1) Start a rubbermaid worm bin - when it comes time to start a real worm farm, you'll have some valuable experience. You don't say where you are, but if your inlaws object to a worm bin in the house, you can stash it in the garage in most climates.
2) Lots of plants will grow in containers, and the experience will come in handy. Looking at decorative plants pleases most people.
3) Is there a patio or deck where you could put up a cold frame or small greenhouse?
4) Besides basic carpentry, learn soldering.
5) Look for local courses in plant propagation, or any subject that applies.
6) Research green homebuilding techniques, and draw many house plans.
7) Get this book -
http://www.chelseagreen.com/bookstore/item/fresh_food_from_small_spaces:paperback - and try something.

Now is a very good time to learn how to can. Everybody likes pickles, jam, relish...Tons of books out there, and the equipment for water bath canning is cheap.