I always make my own bbq sauce. In a pinch I use simmered ketchup as a base- and use whatever else I feel like- molasses, cayenne, onions, garlic, mustard, smoke, chilis, oranges, cumin, thyme, savory, brown sugar, paprika, bourbon, epazote, agave nectar, cider vinegar, tomatos, lemons, sriracha, curry paste, etc -you get the idea.
Fresh BBQ sauce is infinitely better then any crap you buy in the supermarket