This is a great dry rub for beef; we've been using it on flatiron steaks with great success. I temporarily misplaced the recipe, so when I found it I decided it was time to share (plus now I know where to find it in the future!)

Southwest Rub

2 Tbs chili powder
2 Tbs brown sugar
1 Tbs ground cumin
1 garlic clove
2 tsp cider vinegar
1 tsp worcestershire sauce
1/4 tsp red pepper flakes

Combine all ingredients in a small bowl and then rub evenly onto meat to be grilled.