Fly your freak flag, bitches!
I personally have never felt the urge to "fly the flag" in a literal sense, but it does make me smile when I see people expressing themselves like this. Lots of cars in my neighbourhood have rainbow stickers on their windows or bumpers. Quite a few of the stores have rainbow stickers in the windows (although I think that really means Pink Dollar Welcome Here for many, rather than any particular sign of allegiance).
I know there is rhetoric on both sides about acts of proclamation like this, but there is a sentimental side of me that likes to see the old rainbow flag flying. When I was a teenager I would have given my right arm to have known that there were other gay people in my neighbourhood. I think there is an argument for visibility, plus flagwise I love a bit of colour and movement!