It was, in my opinion, a fad that didn’t die soon enough. The Good Idea fairy should have been strangled before she ever opened her mouth and said, “You know, I bet there’s a way to do that without a big outdoor smoker thing, and cheaper!”
I think it started with planked fish and in-restaurant smoker sorts of things. Planked fish sort of made sense, because it did not produce smoke. You took a piece of the proper wood, slightly larger than your piece of fish, and soaked the wood in water. You put whatever spices you wanted on your fish fillet, then set the fillet on the plank. Plank and fillet then went into the oven, usually on a rack with a drip-pan under them, and cooked. The idea was that the fillet picked up flavor from the plank and stayed moist because of the damp wood. The wood did not catch fire or char. I don’t know if this is still done at home, but it seemed trendy for a while. I never tried it. Buying expensive wood just to cook a piece of fish on . . . Not my sort of cooking thing. And DadRed would probably have turned the plank into trim on a project, with a carving on it.
Planked fish (not to be confused with South African planked fruit, which is a type of dried fruit a bit like a thick and sturdy fruit-leather), at least had the virtue of not smoking up the place if done correctly. The stove-top smokers, however . . . What works in a commercial kitchen with lots and lots of high-power ventilation is not so good in a house or apartment, especially when you live in a place that requires smoke detectors that call for help.
The idea is that you have a pan with woodchips or sawdust, a drip-catcher that allows smoke to flow around it, the mesh grill upon which the meat rests, and then a lid (or make a foil tent for larger things). The smoker works like a big outdoor smoker, although it seems to work at a slightly higher temperature. The smoke flows around the meat and does its thing, flavoring and cooking the meat. Some versions have their own heat source, others sit on a burner on your stove. The ratings vary from “I love it” to “don’t try this indoors in a small apartment.” I’d incline to the latter, but I have serious doubts about charring materials in a steel pan or box on my stovetop. Apparently it works well for many users. I only see the down sides, including cleaning the smoke off of every surface in the kitchen. There are lots of surfaces in my kitchen.
One thing I probably should mention if you are inclined to cook brisket in a smoker. Check the size of the brisket in the instructions. Down here, brisket is assumed to be between 8-14 pounds, although I’ve seen 20 lb monsters and larger. (One of the guys said, after we wrestled the beast into the smoker, “Well, we know what happened to Babe the Blue Ox.”) Back east, especially in the northeast, briskets tend to be no larger than 1-3 pounds. You have to specially request a larger brisket. I had no idea of this until reading a thread on-line about ruining briskets and the young lady could not figure out what the problem was. People went over the rub, the cooking time and temp, and finally someone asked how large the brisket was. “A pound and a half.” No wonder she ended up with a lump of charcoal instead of a tender brisket! That was the largest to be found in the NY-NJ area grocery stores. This might be changing, but do check the size of your meat.