This is just a list of easter eggs (that I know of) in this map, as well as an explanation of what they are, you can look up the locations in several YouTube videos. (WARNING, I HAVEN'T PLAYED BIGCITY IN A WHILE, SO I DON'T KNOW IF ALL OF THESE ARE STILL IN THE MAP)

1. Cafe Baltic Screamer
In the map, you can find a place called "Cafe Baltic", pressing E on the door will activate a loud scream (no screamer picture though, just the sound). The scream is actually from the Half Life 2 Beta's Stalkers, which you can spawn from the Combine NPC Tab. Luckily, the scream (and a lot of the Stalker's functionality) was cut from the final game, and all they do now is walk around aimlessly (unless you also spawn a Vortigaunt, then the two will fight)

2. The Garage Door Demon
You can find a type of garage door somewhere in the map that, when activated, will play a slow, deep laugh. The laugh is Father Grigori from Half Life 2 (or the TF2 Heavy, I can't tell due to the slow down, seems like Grigori though) You can spawn him from the Animals NPCs tab, though I doubt he'll do the laugh. You can, however, hear the laugh a few times while playing the chapter "We Don't Go to Ravenholm...", most notably at the end as you're leaving Ravenholm.

3. GNOOOOOOMES!
In a secret room on the map, there is a garden gnome hiding in the dark. Picking him up will have him say "No, NO!" and shooting him will make him scream. The gnome is from Half Life 2: Episode 2, and is essential to the achievement "Little Rocket Man", you can learn about the infamous achievement by clicking here and scrolling down until you find it: http://half-life.wikia.com/wiki/The_Orange_Box_Achievements#Episode_Two The screaming is hardly anything spoopy either, literally just male citizen sound effects from, you guessed it, Half Life 2.

Well, that's it. Looks like I wrote a guide or something, oh well. I just felt like it would be nice for people to know what these are, I feel like things in Gmod tend to be less creepy for me when I can just go "Oh hey, it's just that thing from that other fun game!"


tl;dr, just a list of the easter eggs and what the sounds actually are cuz why not