I wish my toilet was half toilet and half coal stove!
After an exhausting internet search, I've come to realize that not one person has ever invented or proposed a toilet heated by coal!
Well why not? If the toilet was made of cast iron, and you designed and calculated the size and placement of a firebox, you should be able to have a nice warm place to sit and read a magazine.
Now, I admit that a fire located so close to a gas producing appliance such as myself could be dangerous.
I'm willing to take a chance that my pants won't spontaneously combust. But who needs all that hair on their legs anyway!