Wild Wasteland

Wild Wasteland is a trait in Fallout: New Vegas. It adds or changes random encounters or locations which would not appear the same in-game without the trait.

Events that are modified/triggered by Wild Wasteland are indicated by a unique sound and an on-screen "..." message with an image of the Vault Boy with spirals for eyes, identical to the Wild Wasteland image.

Gameplay
There are 15 major Wild Wasteland encounters throughout Fallout: New Vegas. Besides encounters, Wild Wasteland also has a few effects on things that occur in the base game. Although these changes or events are specific to taking the Wild Wasteland trait, their occurrence is not accompanied by the "..." message. The Appendix XIV: Wild Wasteland Oddities section of the Fallout: New Vegas Official Game Guide describes the main encounters in more detail and is where the main encounters are named.

Main encounters
Listed in Fallout: New Vegas Official Game Guide; Wild Wasteland Oddities p. 448 

Witch! Witch!
If the Courier's reputation with Freeside is Vilified, some Freeside residents may tell them "Witch! Witch! You should be burned for all the people you've turned into newts!"

Get an Axe!
When Dean Domino kills his first ghost person he will say, "he's not dead... it's a trick. Get an axe."

Are you my mummy?
In the wine cellar near the bell tower from which the Gala Event is triggered, the phrase "I AM NOT YOUR MUMMY" is scrawled on the central pillar.

Two-Bears-High-Fiving
A member of the Dead Horses named Two-Bears-High-Fiving will rush out of the Angel cave and pump the air with his fist.

Stripe
Behind Dr. Borous' house in Higgs Village is a dog house containing a miniature deathclaw named Stripe.

...And then Explode and Die
Inside X-7a "Left Field" Artillery Launch, the Courier will hear a garbled intercom message that ends with "...and then explode and die."

Dogs Playing Poker
In the X-8 research center, after exiting the high school testing area, is a room with a window that looks into another room containing five police cyberdogs sitting around a table littered with cards, poker chips and alcohol.

Wolverines!
In the X-8 research center's high school testing area, the word "Wolverines" has been spelled out on a wall.

Hi-ho! Hi-ho! It's off to work we go!
At the construction site, there are seven intact garden gnomes positioned around the large red crystals, along with pickaxes and lanterns.

Hey, who turned out the lights?!
At multiple locations, including the X-12 research center and the Z-43 innovative toxins plant, it is possible to hear a trauma override harness say "Hey, who turned out the lights?!"

Rokit 88
Slightly northeast of the Big MT west tunnel is an abandoned military truck that has been cut in half by a hill. The truck's cargo bed contains several barrels of radioactive waste and it has a New Jersey license plate that reads "Rokit 88."

Kilroy Was Here
As one exits The Think Tank or The Sink, turn left and follow the dome's wall. On the wall is a piece of graffiti that reads "Kilroy was here."

Seymour
A petrified corpse of a dog named Seymour can be found in the Cave of the Abaddon on the right side from the entrance next to Sunflower Summers' corpse on top of a turned over cabinet.

North Rawr
When crafting the Fist of Rawr, it will be renamed Fist of the North Rawr.

Try "Guest"
The password to the terminal at Third Street Municipal Building is "Guest."

Credits
The credits appear differently with the trait, listed in the game files as "CreditsWacky."

Behind the scenes

 * In an interview on Gametrailers, Chris Avellone noted that the Wild Wasteland trait adds more references to older content in Fallout and Fallout 2, in regards to special encounters.
 * According to Joshua Sawyer, the trait was added as a compromise between members of the team who suggested "wacky" content and those who thought such content would be out of place within the game's tone. Sawyer was also worried that if it was flipped on and off through the use of console commands, it would cause bugs, so he made the decision to have Wild Wasteland as an optional trait.
 * Justin Bell was responsible for creating and implementing the Wild Wasteland musical sound effect.

Bugs

 * The special dialogue on the NCR emergency radio channel may be processed while there are no radios tuned in to the station, causing the "..." message to appear for seemingly no reason.
 * The "..." message will not appear when finding the 'I am not your mummy' message.
 * After removing the Wild Wasteland perk in The Sink, the poker playing dogs will revert to the non-Wild Wasteland state, even if previously visited the X-8 facility.