In 2011 I had an idea for a ceramic coffee mug with a threaded base. then build a screw on base with heating element, battery, and QI charger. Screw the base on, set it on a QI charge pad... voila "always hot coffee". When you're done for the day, unscrew the base, put the mug in the dishwasher. Rinse, repeat.

For a year I researched getting a prototype built, castings, etc. Finally decided to just abandon it. Just drink coffee faster and it won't get cold.

Now I have 2 Ember mugs and an Ember travel thermos. Still can't dishwash it, but dang it's useful.