Rio de Janeiro
Miami: Any bars that play hip hop/90s?
Club Play, or Eve (aka white room).
Chicago: Fun stuff
Museum of Science and Industry is very nice, ice skating on millenium park is really nice, if there isnt too much cold you could rent some bikes and go around, also check the navy pier.
Chicago: airport transportation
By train, the Blue line takes you directly from O'Hare to downtown, and is about 10 times cheaper than any other way.