The MIT computer lab used to forgo passwords. If you wanted to dick with the system you could, so it removed the thrill of "breaking in". You could mess with other people's accounts but they could mess with yours, too. Kind of like how everyone in Texas carries guns starting in kindergarten and so everyone is really polite.
I think it's a great lesson so I think I'll make my startup's vital information globally accessible (admin functions, source code, even my billing info for the ISP) and trust to my fellow human beings' goodwill.