Have you checked the Facebook real identity card project ? If yes there is one for Google + too but not a real identity plastic card but a image of a Google + card that can be used to print out a actual plastic or business card its simple Just follow these steps:
- Go to http://hangoutgraphics.com/idcard/
- Enter your Google+ ID
- Enter your nickname
- Enter the date you first joined Google+
- Hit generate and it will download your ID card. this is what it looks like
