AsteriskLabs/devise_google_authenticator — pull request #12 by blahblahblah- (2013-12-09 18:23:56+00:00)
Title: Added ability to not require token for a user if they have logged in recently

Users that have logged in recently with a token is not asked again with the same device until a specified time has passed, similar to what happens with Gmail. By default, this value is a month.