Well the old mail box post had the mailbox mounted on a platform that was hinged so that if the snow plows pushed snow on it, the platform would just flip and let the snow flow around it. That works for, probably 10-15 years. The last snow this year was just so wet and heavy it snapped the post itself.
So after considering a number of options, I built one that rotates so it is parallel to the road during snow storms. It has a steel rod holding the top and bottom pieces together that rotates on a bearing.

So here it is in normal position.

And here it is ready for the snow.