AuthLite Interactive Documentation
Quick Start: Install and protect Domain Admins AuthLite Features Supported Tokens Installation and Upgrading Configuration Token Management How to Log In

YubiKeys are ideal for any use case where the computer will have a USB port.  Offline logons to laptops disconnected from the LAN work most easily with YubiKeys as well.

Google Authenticator (or other soft token app) is a great choice if you need to save money on the cost of tokens for some users, or if you need to authenticate at systems where a USB port is not available.

When neither of these options is appropriate (no USB devices allowed, no smart phones allowed) you can use a battery-powered LCD displaying OATH token