Floating crabs have opened up a whole new world of permit fishing. While not always productive, when the permit zero in on floating crabs, it can be downright electric and irresistible for a fish considered to be one of the hardest to catch in saltwater fly fishing. Rainy&';s flostam crab is one of the newest floating crabs on the market, and a must-try for anyone hoping to catch a unicorn -- a permit on a dry fly.