Do I want a weathervane?

One of those little existential questions: would my life be improved by the possession of a weathervane? Or would this simply be the addition of a piece of copper to the roof for no particular reason? Oddly, given my usual desire to avoid frippery, I think it would indeed be a useful addition and am thus looking through the various designs. This one has caught my eye so far: mostly I think because I've really always wonted to live in a lighthouse. Weird ambition but everyone has to have one, right?

OK, so that explains the design, but why would one or other of the available desgins of weathervanes add to my utility, provide me with more than simply the pleasure of bing able to look up and say "Oooh, Lovely!"? Well, there's two reasons there, both really quite practical. If the wind is from the south where we are it's coming from a desert a couple of hundred miles away. A great big desert too, so it's hot. If from the east, from high land, so it's quite cold: a north wind everyone knows and from the west here itis coming over a couple of thousand miles of ocean. So we really do get very different weather dependent upon which way the wind is blowing. Knowing what to expect has its uses.

The other is something I'm not sure about: would a weathervane also act as a lightning conductor? Or could it be made to do so? I have to assume yes: it's a lump of metal on the roof after all and a conducting strip could be run down the side of the building easily enough. For I've twice had the house struck by lightning (we're on the brow of a hill) and both times the strike blew out the phone lines and the internet.

So it's not just the idea of having a pretty lump of metal on the roof, it's having any lump of metal on the roof that sounds like a good idea.