My parents had one made for this place that represents a horseman jumping a gate. It eventually fell off the roof and is now in pieces. I haven't moved to have it put back. We're no longer a horse-owning or even particularly horsey family; that era is over.
I like vanes but I've never figured out how they work. When the arrow points north (say) does that mean the wind is blowing towards or from that direction? I've also never really figured out why anyone- outside of certain specialised occupations- sailors and cricketers for instance- would need to have that information.
Right now the wind is blowing from the north. I don't need a vane to tell me this; the drop in the temperature is enough.
I remember sitting in a classroom as a little kid- bent over an exercise book doing sums or drawing contour lines- and every so often glancing up to see the vane spinning on a nearby summer house. Ah, to be out in that wind...