Late Night eats
Late night means you're only going to get diners (not that this is a bad thing!): Landmark Diner (walking distance), the Majestic (short drive, late-night Atlanta institution), or Waffle Houses (there's one in Underground, and they are also ubiquitous and a short drive in pretty much any direction).
60 Luckie St NW, Atlanta, GA 30303
1031 Ponce De Leon Ave NE, Atlanta, GA 30306
Holeman & Finch (til 1)
Hong Kong Harbour (think midnight weeknights, later on the weekend)
Taco Cabana (can be pretty grungy but it used to be open 24hrs; I'm a one-note orderer- green chicken enchilada platter w/ their thick, chewy housemade tortillas)
There are some taquerias up on Buford Hwy that are open similarly late, depending on the day of the week.
Hong Kong Harbour Restaurant
2184 Cheshire Bridge Rd NE, Atlanta, GA 30324
1895 Piedmont Ave NE, Atlanta, GA 30324