I think the pepper spray idea is good. And I always carry a cell phone, but it's in my under the seat bag and I'm not sure i could reach it very quickly. I certainly don't wear suggestive clothing when I ride...I'm not giving up my spandex shorts and the biking jersey I wear is feminine, but not tight or anything, it's actually a little big and baggy on me. And I can't help my ponytail.
It is just so sad that we have all come to expect this type of harrassment and it's not fair.
It's only worth it if you're having fun