[REQ] Identity confirmation before login to admin accounts

[TonyFloe]

I'm looking for a hack, which forces an administrator to verify his/her identity on a specific computer.

SalesForce.com has a similar system, it works as follows:

Identity Confirmation - developer.force.com

1. [Web UI] Login Activation - In order to login into Salesforce.com using a web browser, the user will need to activate his/her computer. This is done by clicking on an email link received after first successful login attempt. Once the link has been selected, the security authentication will be activated and the user will now be able to login into Salesforce.com from that computer.

I'm not sure if there's a hack which works this way, but if there's, I would appreciate very much if somebody can write it's name.