At a time when well-heeled tech executives are converting mansions into communes, their younger counterparts are glomming onto the same cooperative ideals — albeit in a slightly less opulent form. Even as high-priced, communal citadels sprout up in Alamo Square, funkier co-living spaces are appearing in the Mission, featuring dorm-style rooms, roof decks, and extremely limited street parking. The best among these is 20Mission, a 41-room complex founded by Bitcoin trader and entrepreneur Jered Kenna, who recruited an international group of start-up founders and artists to coexist there. With a chicken coop, shared kitchen, and commanding view of the city's downtown, it has the feel of university student housing — the residents are young, the parties are crowded, the idealism is embedded in the architecture. And here's another perk: Kenna accepts rent in Bitcoin.