Has anyone had any experience with the "Electro-Lube Green" oil filter. It's been around for years, mostly in truck fleets though. It constantly refines the oil so you never have to change it again; only change the filter every 25,000 miles. They claim an increase in MPG by using it. Sounds feasible, since your always driving with fresh oil, less friction, less wear, more MPG.
Electro-Lube Green - AG Van & Truck Equipment