Last year I bought an American made Fatsco Pet Stove to fit into a tiny campervan, they can be mounted on a shelf/plinth if floor space is restricted, a technique favoured by live aboard boaters.
Works with charcoal briquettes (including smokeless briquettes) and wood. I bought mine direct from the lovely people at Fatsco.com.
Here's a pic of one with a pint water bottle for scale.
