Better than traditional multi-factor authentication - none of the fuss. Go Keyless. Keyless-U2F supports Google, Facebook, Salesforce, Github, and Okta SSO.
Setting up with Google : https://support.google.com/accounts/answer/6103534?hl=en&ref_topic=6103521
Setting up with Facebook: https://www.facebook.com/help/401566786855239
Setting up with Github: https://help.github.com/articles/configuring-two-factor-authentication-via-fido-u2f/
Setting up with Okta: http://keyless-tech.com/keyless-okta/
Setting up with Salesforce: https://help.salesforce.com/articleView?id=security_u2f_enable.htm&type=0