A coworker brought in some delicious smoked ribs they'd made and what had the whole office talking was his sauce! It's just something he found online and we agreed it was PERFECT. It has everything you want in a sauce: it's sweet and spicy and flavorful.
I looked it up myself and made a batch last night. It was really good but the recipe I used called for a half cup of Tabasco sauce. I love Tabasco sauce, but that was too much. So the one below calls for a quarter cup.
We also talked a bit about how some of the Texas Jack recipes encourage you to boil the sauce together. The only purpose of this we could deduce would be to create a thicker sauce, or perhaps to get rid of alcohol in the whiskey. We like the kick of the alcohol, so neither of us boil it.

2 cups ketchup
1/4 cup Tabasco sauce
1/4 cup Dijon mustard
1/4 cup whiskey (recipe specifies Jack Daniel's)
1/4 cup molasses
2 tablespoons dark brown sugar
1 tablespoon Worcestershire sauce
1 1/2 teaspoons garlic powder
1/4 teaspoon liquid smoke

If you're just not into making your own sauce, allow me to recommend my favorite bottled sauce: Sweet Baby Ray's. To be honest, it has little in common with Texas Jack sauce, but I love it and buy several bottles whenever it's on sale.