The time that stands out in my mind was the FA Cup 4th round replay at the City Ground back in 1991.
Newcastle were stunned by a late fight back in the first game at St James' Park and Nottingham Forest grabbed two late goals after Mark McGhee and Micky Quinn had put us 2-0 up.
So it was a trip to Nottingham five days later, a match Forest won 3-0.
But, after no provocation whatsoever, when the Reds scored the third goal Keane ran to the Newcastle fans making a hand gesture shouting "You Geordie w***ers!"
The stewards were at full stretch to stop a section of the crowd getting onto the pitch ... and I have to admit ... I was one of them.
Eric Cantona was banned for nine months in 1995 for his kung fu kick on a Crystal Palace fan after he reacted to being targeted having been sent off at Selhurst Park.
18/2/91 - The Day I Wanted To Put Roy Keane's 'Lamps Out'!
Keane: "I don't think I've ever reacted to a crowd but I think you should be allowed to give a little back.
"I wanted to do an Eric Cantona loads of times. I wanted to do it everywhere. Eventually, Eric just thought, 'Enough is enough'.
"In other sports we've seen people go into the crowd and fighting people. I don't sit there shocked. You can see people have had enough."
And what about that incident at the City Ground? I'd LOVE to know what he thinks of it now.