OK...I'm intrigued. In the past year I've really got a hankerin' for grilling and can smoke up a pretty mean baby back rib (so I'm told). But this Butt looks great!
So, where can I get some details on the rub, the time\internal temperature, and the whole paper towel and cooler thing?
Rub recipes abound on the interwebs. Mine is nothing special. Salt, pepper, brown sugar, paprika and whatever else I might pull out of the spice shelf.
Time is driven by internal meat temperature, which is driven by smoker temperature. Figure on 12 hours, give or take.
For best results, your smoker should be between 220-250. I've got one thermometer on the lid and one inside on the grill next to the meat. I also use a battery powered meat thermometer that I stick into the meat around the 6 hour mark.
The meat temp will hover around 150-160 for hours on end. This is a good thing. The heat is breaking down the fat into a liquid. Once this phase is completed, the internal meat temp will begin to rise. I usually pull it off 185-190.
This is when the butts are wrapped in a towel. I said paper towel earlier, but I meant kitchen towel. A paper towel would fall apart. The purpose of wrapping and resting in a cooler is to allow the liquid to be absorbed by the meat. The cooler will keep the butts hot so there is no coagulation.
Those are the basics, and I'm sure you could find at least one person to argue every point, but it works for me.
There are many websites and forums dedicated to bbq on the webs. Google "smoke ring" for a start.