I useit to use gels / bars / sports drink / nuun for all my long rides
now I use some sports drink, but also regularly use orange/grapefruit cordial, hot x buns, malt loaf, marmalade sandwiches, etc. I carry a couple of gels for emergencies. Diluted coke works well for sports drink replenishment on the go.
I make rice cakes from a book called 'feed zone portables' - lots of real food ideas in there
I generally buy gels / sports drink in bulk when various sites have sales