| I turned my old gas BBQ grill into a cold smoker. The racks are in there, and I can put upwards to pounds of bacon in it on three levels. I made a smoke generator out of a piece of flexible water heater vent. I screwed one end to a hole I cut in the bottom of the grill. The other end goes into the top of a large metal popcorn can that serves as the smoke chamber. My smoke generator is an old cast iron frying pan on top of an electric hot plate. Works like a freaking champ. To date I've smoked nearly 50 pounds of bacon, about 30 pounds of sausage, some turkey legs, and some sharp cheddar cheese. If, however, you're talking about a hot smoker, as opposed to a cold smoker like the one I made, you're going to need a substantial firebox on the side to get the heat up to the proper levels. My suggestion would be to use dampers to control your heat levels if you want to use wood or charcoal. Electric could be easily controlled with a rheostat. As for gas, I wouldn't suggest it. Gas creates water vapor when it burns, and I've found that that can really interfere with the smoke flavor. | 
