Box.com and its login integration. They did the SAML communication (or whatever they use) really well. As a result, visiting their URL at yourbusiness.box.com w

Box.com and its login integration. They did the SAML communication (or whatever they use) really well. As a result, visiting their URL at yourbusiness.box.com will redirect your to your company's authorization page where you can supply your native login credentials, two-factor auth, etc that you're already used to.