The users need to register their printers with Google’s Cloud Service and associate them to their Gmail account.

The service
After doing this, the users can get print outs of their mail and selected attachments, which can be in any format.

The registration process is quite simple. The users are required to download a special beta version of the Google Chrome from the website of Cloud Print and install it on the computer attached to the printer, which the users want to be available for the service.