Josh Anvil and the Cypress Door question

I don't want to commit myself to what I'd absolutely choose, because I'd feel that I ought to pick something that'd help humanity. ;) But, over the last few years, what I've fantasized about was the idea of having a home that I could carry in a backpack, so wherever I traveled, I could just take one more step, and be in my home. And I'd just use it in the obvious way, to travel, and have my home and garden wherever I went. (I wouldn't bother with the nefarious possibilities!)