Cut pork butt into largish chunks.
Coat the meat in your favourite rub and place in slow cooker.
Pour in liquid smoke.
Cover and cook 5-6 hours on high, or 10-12 hours on low.
Transfer meat onto cookie tray or cutting board, let cool, and shred (I use two forks, one in each hand, and pull the meat apart that way).
Serve on fave buns or bread with BBQ sauce.