Cook linguine according to package instructions. In medium saucepan, melt butter over medium heat. Stir in flour until the mixture has a "sandy" appearance. Do NOT allow it to change colors. After 45 to 60 seconds, whisk in half & half. Blend until a thick sauce forms. Stir in parmesan and season to taste. Reduce heat to low. Add crab meat. Simmer until crab is heated through. Divide linguine into two bowls and pour even amounts of sauce over the top. Sprinkle cayenne pepper, to taste. Enjoy!