Most broadbrimmed hats will work as long as they've got a strap under
the chin. I have a big straw hat I like, and I also keep a visor in
the convertible just in case. It's got an adjustable back so I can get
it tight enough not to blow off, BUT it's not as good at sun protection
since I've got short hair, and a visor doesn't do anything to keep the
back of my neck from getting sunburned.
I found a neat lightcotton broadbrimmed hat someplace that somehow
folds in on itself to fit into a tiny little bag. It's got a wire core
to give the brim shape, like an underwire bra, but it collapses
figure8 style in on itself, quite novel and handy to throw in a
suitcase or beach bag.
My husband has an "ultimate hat" (ultimatehat.com) which has an
interesting double strap. It can either tie under your chin, or go back
under the bulge at the back of your skull like a mountie hat. That may
not be quite as secure in a high wind, but it's less dorkylooking.
He's got the "original", but I see that now they have a lot more
options.
Anyone have any suggestions for a hat to wear driving now that top down
season is upon us?