I have learned that the success to a dry rub is brown sugar. I used to just rub the spices into the meat and hope for the best. Now I mix the spices at least half-and-half with brown sugar and let the magic happen.
Here's a mixture of the following stuff:
Mix a tablespoon of this with a tablespoon of brown sugar and you've got Rub Magic.
Spread it on neat and you've got Salty Nastiness.
Here's what it looks like after an hour or so of resting in the fridge:
Of course, if you don't want to risk making your own rub, check out the professionals like my friend Shane of Payne County.
Here's his stuff which he recommends cutting with brown sugar. Like the Stones said, brown sugar.