Here's a rub that I use on pork shoulders among other meats.
1 cup brown sugar
1 ½ TBS chili powder
1 ½ TBS garlic powder
½ cup paprika
2 ½ TBS salt
2 ½ TBS ground black pepper
1 tsp cayenne pepper
1 ½ TBS onion powder
I mix all of the above and force it through a sieve to break up the brown sugar. I store it in a air tight container. Shake container well before using.