Male Restroom Etiquette

While the Wondrous Ladies' Room may be a place for chatting, primping, and various Women's Mysteries, the men's restroom is a place dedicated to speed and efficiency. When using the restroom, men must observe certain unspoken guidelines that dictate their behavior therein and speed up the process of using the lavatory. Except in extenuating circumstances, such as overcrowding, any breach of these guidelines is discouraged and can lead to some awkward and embarrassing situations.

Keep all interaction to a bare minimum. Do not make eye contact with other men, as this may be interpreted as an unwelcome invitation. Also, never let your gaze wander to any body part of another occupant, whether or not he is of any genuine interest to you.
When selecting a urinal, stay as far away from other men as possible, so as to better comply with the previous rule. If the only available urinals are adjacent to ones currently in use, use a stall.
Avoid making unnecessary noises. While grunting is never appropriate, the occasional cough is usually all right, though there is always the chance that this could be misinterpreted, as per rule number 1.
And finally, the one rule that must never, ever, be broken: Never say a single word while within the restroom. Not only is it an unnecessary noise, but it grates against the philosophy of speed and efficiency that governs Male Restroom Etiquette. It slows down the transaction process and makes using the restroom awkward and unpleasant for other occupants.

Whenever Male Restroom Etiquette is brought up in media, it is usually Played for Laughs as we watch some poor soul try to use the restroom while another man shows complete disregard for the above rules. And while many men can attest that these rules are indeed Truth in Television, most know that a breach of these rules is not so awkward as some make it out to be. Contrast The Can Kicked Him, the ultimate breach of etiquette.

Examples of Male Restroom Etiquette include:

Comic Books

Often referred to in Sid the Sexist in Viz, which also makes up some rules:
- Can't use the urinal until you've drunk 10 pints of beer.
- Anything more than three shakes is a wank.
One one-page gag of the comic Le Petit Spirou was dedicated to this.

Film

Real Genius: The hyperactive Jordan finds Mitch at a urinal and obliviously bombards Mitch with questions. Doesn't help rather shy 15-year-old Mitch's composure in this situation that Jordan is female.
Spaceballs: President Skroob gets a phone call while in the restroom.

Literature

Mentioned repeatedly in Isaac Asimov's The Caves of Steel and its sequels. In the society of the future Earth, the women's "Personals" are social centers, but the men adhere strictly to the no-interaction rule.

Live-Action TV

House and Wilson are often seen being quite loose about this; they often chat in the bathroom. However, when House gets some kind of bladder constipation and goes into the bathroom with Wilson and pretends to use the urinal but doesn't pee, that's treated as wrong.
Mentioned in Roseanne when Roseanne dresses as a guy and goes to a urinal. After unsuccessfully trying to start a conversation... "Oh! It's like an elevator!"
Averted hard in Babylon 5, where Garibaldi would from time to time have actually discussions with both Sinclair and Sheridan while... using the facilities.
On How I Met Your Mother Ted and Barney actually met at the urinal. Barney thinks nothing at all of chatting with another guy mid-stream and instantly forming a friendship with him, while Ted struggles to be polite while barely saying anything and avoiding eye contact.
NCIS: Flagrantly disregarded by Ziva who (aside from being in there in the first place) has occasionally cornered Toni in the men's room for a heart-to-heart.

Tony: How long have you been standing there?
Ziva: Long enough to know you hydrated well for the desert.

Video Games

In Custom Robo, Harry has to go to the bathroom when nearing the Big Bad. You can choose whether or not to follow. If you go in, two Mooks will confront you after using the urinals. Harry makes a comment about them not washing their hands.

Web Comics

PvP: Skull breaks rule #4.
There's one Questionable Content strip where Marten describes Steve trying to talk to and look at him while they're peeing as "the creepiest thing a dude can do to another guy at the urinals".

Web Original

This YouTube video explains these rules in greater detail and links them to the very fabric of our civilization.
Deconstructed using the power of math here in the xkcd blog.
The Urinal Game.

Real Life

Violated by U.S. President Lyndon B. Johnson, who would discuss business with people while he was on the john (note, in person, not on the phone, with the door open). It is unknown whether he did this because he was genuinely uncaring about the whole thing or as part of a power trip showing off that he was the boss and you had to deal with him even while he was on the toilet.
In Mel Blanc's autobiography, he talks about his son Noel coming in, sitting on his lap, and making Mel read to him, even when he was on "the can".