Max Payne 2: The Fall of Max Payne Cheats

To find this easter egg, go to Act 1, Chapter 7 continued. ("A Sign of Her Passage")
After the part where you slo-mo shoot the guy off the window cleaners lift, climb down the scaffolding until you reach the window where a man is blasted through. Instead of going in the window, do a dive to the ledge opposite it. Head around the side of the building to find the easter egg.

You will find a piano twice in the game, once in Part 1, chapter 7 and once in Part 3, chapter 7. Go up and start playing it and Max will play a bad version of the theme tune