Wow. This topic has really been great food for thought for me. Though I don't know if it would work in New England where I live, in Missouri or somewhere south or west, giant Mongolian sunflower could be planted with buffalo gourd and some kind of bean to form a 3 sisters kind of partnership that provides oil, protein, fuel and/or ethanol system stock. (Seeds and fuel from the sunflowers; seeds, biomass/forage, and roots from the gourd.) I'm not sure what the best bean would be, but a prolific bean (scarlet runner?) could be added for nitrogen fixing and more productivity like R Ranson suggested. White clover could be added as a lower level ground cover and N fixer, and comfrey for extra nutrients (and forage/ethanol stock)--and, frankly just to have something interesting before August/September. If you could take the thorns: mesquite, honey locust and/or osage orange could be added as tree and overstory for extra pods/seeds and fuel wood/building material.
In New England, I don't think buffalo gourd would do so well--does anyone know? I've not tried it here yet. I may do this and just grow butternuts because the rest (minus the mesquite option) would work fine here.