The dealers around here give out free samples, I've been offered free hits walking through the city at night before, they give you a free "present" and reel you in till your hooked. (im talking about straight heroin though)
For Fourth of July one year [when I used to smoke cigs], I ground up a flint and rolled all my cigs in the dust. It turned all my cigs into little ciggy sparklers. Everyone loved them. lol