YubiKey provides an interesting feature called Scan code mode. You can use the "Scan code mode" feature available under the static YubiKey configuration of the YubiKey configuration utility to program the YubiKey 2.0 to emit your own password (of up to 16 characters in YubiKey 2.1.2 and up to 38 characters in YubiKey 2.2) containing alphanumeric characters.
For reprogramming the YubiKey in the Scan code mode static password follow the steps given below:
1. Insert the first YubiKey to the USB port and start the YubiKey Configuration Utility
2. Select the "Create a static YubiKey configuration (password mode)" from the Select task screen
3. Select the "Scan code mode" option
4. In the same screen enter your desired password in the "Scan code input" field
5. From the "Specify output parameters" screen, select the appropriate parameters (All parameters are optional)
6. From the "Specify configuration protection" screen, select the appropriate option
7. From the Programming screen, select "Write to configuration 2 (YubiKey 2 only)" and click on Run so that you can use the factory programmed first configuration slot with online Yubico OTP validation server and second configuration slot for you own purpose. If you want then you can reprogram the first configuration slot as well.
We hope this helps!