A widget that shows Google+ Activities. Specify the G+ id and the API Key, and place it on your blog template, and the widget does the rest.
gplus is a WordPress Plugin.
It provides a WordPress Widget that displays a list of your recent Google+ activities in the sidebar. The plugin uses the Google+ API, and authenticates via an API key that YOU (the installer) acquire via the Google API Console.
Because it uses the public REST API of Google+ that Google documents and supports, this plugin is very reliable and simple. (Other WordPress widgets that say they show Google+ activity have relied on screen-scraping, which makes them brittle and unreliable.)