Cook pasta according to package directions, omitting salt and fat.
Drain.
Place pasta in a large bowl; keep warm.
Melt butter in a large skillet over medium-high heat.
Add onion; saut 3 minutes, stirring occasionally.
Add garlic and tomatoes; saut 2 minutes, stirring constantly.
Sprinkle shrimp with Cajun seasoning, red pepper, and salt.
Add shrimp mixture to pan; saut 3 minutes or until shrimp are almost done; remove from heat. Stir in half-and-half.
Pour shrimp mixture over pasta; toss.
Sprinkle with parsley.
Wine note: Linguine with Spicy Shrimp combines peppery heat with a creamy sauce, making a fuller-bodied white a good partner. Little Penguin Chardonnay 2008 ($6), from Australia, has tropical and pear fruit, with just a bit of sweetness and refreshing acidity. --Jeffery Lindenmuth