We've been doing password-less entry for years over SSH with certificates. You generate a key, share the public parts and do some magic with your private parts

We've been doing password-less entry for years over SSH with certificates. You generate a key, share the public parts and do some magic with your private parts (ahem) and it all works. What I think the OP is looking for is a similar pattern for the web and browsers. Is there no way we could use the FileAPI to check for a keyfile? http://caniuse.com/fileapi http://caniuse.com/fileapi