O.M.A.C.: the one Man Army Corps, was the last of Jack Kirby's DC work, and it was also by far the strangest. The story takes place in "the world's that coming" (a line that never seems to get old), in which Buddy Blank has been molecularly altered by an intelligent satellite named Brother Eye into becoming a one man peacekeeping force. Together with the Global Peace Agency (comprised of legions of faceless (in order to appear raceless and thus completely neutral) they battle legions of super rich gangsters.
The concept gives Kirby lots of room to let his imagination fly, and the result is a sort of stream of consciousness wonder that I don't believe was matched until Grant Morrison came along (Kirby was a huge influence on his work). OMAC confronts subway mutants, pseudo people, and in my favorite issue an entire city that is rented out as a deathtrap.
The only fault with the book is the way it ends. After 8 issues, Kirby finally ended his time at DC to return home to Marvel (where he worked on Captain America, Black Panther, and the Eternals). And since the sales weren't that good on the book (it was far too ahead of its time), DC changed the final panel so that everyone randomly explodes. It's very surreal, but not in a good way. Otherwise I think I actually preferred this book to much of the Fourth World books Kirby worked on during the same period.