I ran across this recipe on the internet (allrecipes.com, maybe?) and made a few modifications to it. This is one of the best BBQ sauces I've ever had. A little sweet, and a lot spicy. The original recipe said to use 1/2 tablespoon of ground chili pepper. I think the 1 1/2 tablespoons is better, but feel free to turn down the heat if you want.
2 1/4 tablespoons vegetable oil
1/2 cup minced onion
1 1/2 cups beer (IPA is a good choice)
6 oz can tomato paste
1/2 cup white vinegar
1/2 cup brown sugar
2 1/2 tablespoons honey
2 tablespoons Worcestershire sauce
2 teaspoons salt
1/4 teaspoon coarsely ground black pepper
2 tablespoons whiskey
2 teaspoons garlic powder
1/4 teaspoon paprika
1/2 teaspoon onion powder
1 tablespoon dark molasses
1 1/2 tablespoon ground red chile pepper
Heat oil in a medium saucepan over medium heat. Cook and stir the onions in oil for 5 minutes. Stir in beer, tomato paste, vinegar, brown sugar, honey, and Worcestershire sauce. Add remaining ingredients. Bring mixture to a boil, then reduce heat. Simmer for 2 hours, uncovered, or until sauce thickens. Use right away, or store in a jar in the refrigerator for up to a month.
Edit: I found the original recipe on allrecipes.com.