Free product idea: Here in NZ, and I suspect other places with lower quality housing, lots of people use electric resistance heaters, and also have problems with damp air and/or dehumidifiers.

How about a solid state dehumidifier+heater using peltlier elements?

A dehumidifier is basically an air/air heat pump, with the cold side optimised for water condensation without freezing, and one issue with them is the noise from the compressor...