sadly, the one on the left tends to become unuseable for 50%+ of people because after 50 years old, your hand grip strength slides downwards. You just can't use that opener anymore past that age.

i have always thought about self sufficiency of housing. i have alwayshoped to see housing which not only was from the natural surroundings, but also gave the owner the means to be self sufficient: garden plot; water extractor; renewable energy power--- and the house itself: i like the idea of hobbit style houses made from local surrounding materials: mud daub walls/roof, maybe a treehouse from wood? But i would be worried about how long the wood would last.