Mystery Solved.

This is mystery plant number 2. It has just one little plantlet on the end of each 'branch'.

They are both from the same family - Kalanchoe daigremontiana - nicknamed Mother of Thousands or Mexican Hat Plant and are a native of Madagascar. Many thanks to new blipper ~beachcombing for solving the mystery for me.

This version is also very attractive and is a much bigger plant, this particular one is about 1.5m tall and I do seem to have an awful lot of this one around the place!