Have you ever heard of a Cajun microwave? I came across these several years ago and the thought has intrigued me ever since. They are basically wooden boxes lined with sheet metal and they have a metal well on top for firing your coals or wood inside.
Meat goes into the box and through convection cooking over several hours you end up with a tender, juicy piece of meat cooked to perfection.
I have even seen some home brewed designs that use kitchen sinks for the metal wells which make the build that much simpler.
Below is a very detailed video of the construction process.
This is getting added to the to-do list for sure.