4: Eric Cantona
Thought of as one of the greatest players to have ever donned the red of United, Cantona was a buy who didn't fall under the category of unearthed gem, but provided goals in abundance.
Signing for United for £1.2million from Leeds, where he had won the English title, the Frenchman almost single-handedly turned their season around, and continued to do so in the years following.
Graceful with the ball, unplayable on his day and, with the exception of his poor disciplinary record, a near perfect footballer.
Cantona was vital in the success Ferguson enjoyed in the 90's and a man whose ego knew no bounds. A bargain if ever there was one.