oh ok
a real bar off.
if some one says a realy stupid comment, then you say oh ok, can also be used if not really listening to what some one says, then they expect an answer and you dont know whether they said something funny or sad.
1) i like fish
   oh ok (u fuking retard)
2) my mum died
   oh ok
3) and then he said wallaboo....hahaha
   oh ok