Not really. There are utilities that sign things (e.g. Signify) but they don't attempt to solve the difficult problem of identity management. Also, OpenPGP is

Not really. There are utilities that sign things (e.g. Signify) but they don't attempt to solve the difficult problem of identity management. Also, OpenPGP is an open published standard with an extensive infrastructure of implementations. It's hard to overcome that with a new proposal.