There are, of course, quite a few crazy designs but there are also real and realistic ships like these:
More than just realistic, there was an actual proposal to finish Illinois (BB-66) with a single funnel and if construction was finished it likely would've been completed as such. The single funnel would've allowed for better AA-gun arcs and IIRC the ship would've been finished with better flag facilities too (either Halsey or Nimitz - I forget who - was basically custom re-designing it into his personal flagship). Though some of the details are off like the prow and complete absence of medium-caliber turrets.