I use YubiKey which is an easy to use two-factor authentication, and Yubico have created a Salesforce app! It utilises the new Login Flows released by Salesforce in Winter ’15 so you can authenticate to Salesforce using a YubiKey!
Login flows allow administrators to build post-authentication processes, you can associate the flow with a user profile, and send the user through that flow as they log in. Some of the things you could use the login flows for are:
- Capture registration information at the point of login
- Provide details of the terms of service with an an acceptance form
- Prompt the user for second factor authentication.
Yubico have created a little example on how to create a a login flow using YubiKey so you can create your own login flow using Salesforce Flow, or if you wanted to write your own UI.
You can also Yubico with a load of different password managers to give extra protection to your passwords (LastPass, Password Safe, Keepass + others) as well as using it for single sign on, CMS’s etc etc…