Also a big fan of Quinoa, however it appears there are some hurdles to cross before it's widely available and remains "cheap"

http://www.nytimes.com/2011/03/20/world/americas/20bolivia.h...

[update] Probably one of the easiest and most nutritious meals I know is some quinoa, chopped veggies and sriracha. Hell, quinoa and sriracha isn't bad in a pinch.