I'll go you one better; hamburgers used to cost 15-cents. (Yes I know I'm dating myself.)
Or how about Crystals (Krystals?, Cristals?) which used to sell burgers for a dime?
But wait!, there's MORE! (Just ask Billy Idol.) You used to be able to eat dirt for free! At least, according to bison_bob, aka dr_zen, aka cbuns, aka idiot_of_a_thousand_yahoo_ids, aka too_many_to_list_here; I just refer to him as meathead.