While perusing my cookbooks, I realised one book I had might interest this group. It's called 'Ratios' and shows how a lot of things you can cook can be broken down into the simple ratios of ingredients. This is especially true for baked goods and batters, but could apply to other things too. Might be handy to know when you're out and about and want to make something without taking scales or measuring equipment.
http://www.amazon.co.uk/Ratio-Simple-Behind-Everyday-Cooking/dp/1416571728
http://www.amazon.co.uk/Ratio-Simple-Behind-Everyday-Cooking/dp/1416571728