I was asked earlier today to create a Google+ widget for a website to replace a twitter widget. I was suprised but also interested to get it working.
Currently there is no widget maker from Google but there is an api which allows you to do the same thing.
I made this pretty quickly, so there are still problems eg, when posts contain videos, but it works.
You will need a google api key which you get through your google account (google it!).
There is practically no styling but there is an included stylesheet that you can modify.
You have the options to limit the amount of posts (1-100), wether to show author info, how to link images and how big images should be.
With a bit of styling I'm sure you could get it working for you! ;)
You can get it from here
There is a demo here with my feed where I was testing it click here (very basic with no styling).
This is given to you with no intention of support so please don't ask me to fix problems with it as it is an experiment!
You are more than welcome to improve it and make it your own.
I also must point out that I made it with the help of codelobster, which has a joomla plugin which creates all the base files needed to create modules and components!