Pork shoulder is an inexpensive cut of meat, and since it cooks slowly at a low temperature, it is also relatively hands-off.
From the book "Mad Hungry," by Lucinda Scala Quinn (Artisan Books).
Source: Mad Hungry, April 2011
10 garlic cloves, peeled
4 tablespoons fresh oregano leaves (from about 5 sprigs), or 2 teapsoons dried oregano
4 tablespoons extra-virgin olive oil
3 whole limes, cut in pieces
1 tablespoon coarse salt
One 7 1/2 pound boneless pork shoulder (also known as pork butt or picnic shoulder)
Puree garlic, oregano, olive oil, limes, and salt in a blender or food processor.
Place meat in a roasting pan, and score the fat on top of the pork. Rub garlic mixture all over pork. Cover and refrigerate overnight or up to 24 hours. Flip roast occasionally and redistribute the rub.
Preheat oven to 250 degrees. Remove meat from refrigerator 30 minutes before cooking. Place pan in the oven, fat side up, and add 1 cup of water to pan. Roast, uncovered, occasionally basting meat with juices and rub and turning pan to promote even cooking. Cook for 6 to 8 hours, until meat easily shreds. Let rest for 15 minutes, then shred and serve.