Wow - thanks to a comment about this, I have now discovered Sock Ring Hair.
The Theory is that you can make a bun ring with a sock. Finally, a use for all those odd socks!
Cut off the toe of the sock, and roll it up into a ring - that's it.
Probably wash it first of course.
But the way of putting your hair up in it, is so nice. You can do this with a normal bun ring of course.
Pop your hair into a ponytail as before. Instead of putting the bun ring at the base, put it on the end of the ponytail and roll all the hair into it, turning the bun ring as it goes down and spreading the hair out.
Much fuller, no need for clips or extra bobbles, it holds itself up. The above is my first attempt and, besides a few flyaways, it looks so full! Someone commented on it when I was in town earlier :-D
Apparantly, if you sleep on it like this, it gives incredible curls. I shall update in the morning on those!