Stumbled across an interesting item on Rockauto.com. It's basically a carb gasket for between carb and intake, and it has 2 small electric heater elements underneath the throttle bores. They come in a variety of configurations, and looks liek the OEM applications were in mid-80s GM cars.
I presume these are for heating the fuel when the engine is cold (for emissions reasons?). The spreadbore / Quadrajet style is only $40, so it's not out of reach as an experiment. Ought to give better MPG in the winter, right? How much of a 'nuisance' to wet flow is it at other times, though???