The Collaborative International Dictionary of English v.0.48:

Money-maker \Mon"ey-mak`er\, n.
   1. One who coins or prints money; also, a counterfeiter of
      money. [R.]
      [1913 Webster]

   2. One who accumulates money or wealth; specifically, one who
      makes money-getting his governing motive.
      [1913 Webster]

WordNet (r) 3.0 (2006):

moneymaker
    n 1: someone who is successful in accumulating wealth
    2: a project that generates a continuous flow of money [syn:
       moneymaker, money-spinner, cash cow]