You could buy a Bradley smoke generator, and for about 200 bucks including an assorted box of their proprietary smoke wood pucks, and some mods to install, you'd be smoking. I can't say for sure if it would add any heat to the smoke chamber or not in terms of actual cold smoking.
It would seem to me that the A-Maze-N-Smoker, for it's simplicity, cost, and no moving parts or electrical needs would be a much better choice, IMO.
I have thought about trying the A-Mazin-N myself. But it has problems at high temps. According to the manufacture it was designed to cold smoke. With my setup I can cold smoke or hot smoke. As far as the cost, it cost me approximately $1.00 per hour to operate. I have tried to figure out how much it cost to operate the A-Mazin-N but it depends on how you many places you ignite it as to how long it last. Also you have to worry about the whole thing igniting and burning up your wood in a short time. I think I'll stick with what I have. $1.00 per hour is no big deal and I get a consistent amount of smoke and it works hot or cold. As I said, if I am at home I use the original wood chip pan anyway.
That is the cost of the wood. If you shop around they can be had for about .30 cents each and are good for about 20 minutes. So about .90 to $1.00 per hour. I guess it depend on what your definition of "WAY" expensive is. It worth it to me to be able to smoke completely unattended if I want to. I can work all day and come home to a perfectly smoked Boston butt any day of the week. It is probably a little more expensive than wood chips which I use if I am going to be home all day. It also allows me to cold smoke without any heat.
I guess I better get busy and design and mfgr something.... that is friggin highway robbery! My estimated cost for a smoke is less than 50 cents! I just figured someone made a smoke box that ran a standard pellet or chip wood.