This is a quote from 1984's Ghostbusters, in which Bill Murray's character 'Peter Venkman' warns the Mayor of the pending fallout from the escaped ghosts:

The opening of an old song called "Dead Man's Party" released in 1985 by the band Oingo Boingo, with the Teenagers behind Halliday being extras from various John Hughes Teen Films:

Various John Hughes films from the 80s

Funeral Parlor

"His surroundings are actually from a scene in the 1989 film Heathers...with all actors and extras from the scene including Winona Ryder and Christian Slater"

Ghostbusters, Indiana Jones and the Temple of Doom, Star Trek 3, The karate Kid released

The sale of the first Macintosh from Apple

Both Quarters on his eyelids are from 1984. Some things from this year include:

Young Halliday

After morphing again into a small boy wearing a faded The Muppet Show T-shirt, with a 21 inch zenith TV, hooked up to an Atari 2600 Game Console (released in 1977)

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His favorite game being Adventure and here is the very first digital Easter Egg: