Birds' brains do not have cerebral cortexes, like mammals. They do have something called the hyperstriatum however. New evidence suggests that, despite this structural difference, birds have evolved the capacity to dream - at least the Zebra Finch has. How... cool... is... THAT!?!
Humans sometimes dream of flying. Do birds dream of playing the piano? Eating a taco? (Grackles, gulls, and corvids do just fine at that already, eh?) Driving? Capturing humans and putting them in cages? Take a gander at the links below, talk amongst yourselves, and let me know what you think.