Add a +1 button to the site: http://www.google.com/intl/en/webmasters/+1/button/index.html and/or a Plus Badge for the page: https://developers.google.com/+/plugins/badge/config?pageId=108004957863691723960&hl=en
OpenID is service that allows you to log-on to many different websites using a single indentity. Find out more about OpenID and how to get an OpenID enabled account.