1. If you don't finish all sentences with "AAAANH" (example: "Turn rightAAAANH") no rickshaw driver will understand you.
2. If a street is one way, it is not a traffic violation to go in the "wrong" way if you keep close to its edge.
3. If a store is not named with one (or a combination) of "Sri", "Ram", "Rama", "Ganesh" or "Krishna", the government probably will close it.
4. Mad Max apocalyptic landscape was based in a milder version of Chennai.
5. It is not possible to negotiate with any rickshaw driver below a minimum amount that apparently they all have in their minds. It is possible to pay MORE though.
6. Buses do not need to stop at the stops, even if people are going in and out. People have to run and jump on the bus. That is why the common Chennaier is so thin.
7. If you are out at night, the police can beat you. That is the law.
8. Chuck Norris once said "I cannot live in Chennai, I can't take the heat".
9. It doesn't matter that you are white, blonde, have a huge camera hanging on your neck, a map on your hand and have a colorful sign saying "tourist, not from here" pointing at your head, people will still stop you to ask directions (in Tamil) for some obscure place.
10. When people don't know the way to a place they are asked for directions, it is polite to direct the person is some random direction.
11. When a hole (that is too big for a car to drive by) appears on the road, instead of fixing it, the proper course of action is to put some rocks around and a few plants. Chennaiers appreciate their road gardens.
12. When a car (or any other vehicle) honks, it is not saying "get out of the way", it is merely saying "hey, I am here" or "hey, I will do something you don't expect, like turn".
13. Chennai is one of the most advanced cities in the field of quantum spacial physics: anywhere where there are only space to fit N, in Chennai it fits AT LEAST N+1. (Example: on the road I cross everyday, there are 4 lanes, but it fits approximately 4 lanes of cars, 1 with pedestrians and 1 with vehicles going on the "wrong" way).
14. Chennai is one of the greenest cities in the world: everyday there is at least one light shortage to help the people go green.
15. If you ask a rickshaw driver if he knows the address (even if you invent the address), he will always says "ok" or "yes".
16. When there is a birthday, people celebrate by putting cake on the face of the person who has birthday.
17. Chennai is in the Guinness World Records Book as the most amounts of signatures needed to open a bank account. It is rumored that you could make a bridge from Chennai to the Moon with the amount of papers one need to sign (in 4 or 5 different places in the same sheet).
18. Going to the beach in Chennai does not mean bathing, even though it is constantly 40 degrees.
19. Men use skirts much shorter than the ones designed for women.
20. It doesn't matter how many friends you have, once in Chennai, your biggest amount of SMS received will be advertising.
21. Chennai is the only place where you need to look 360 degrees to cross the street.
22. When cars almost collide, no one gets angry, it is just business as usual.
23. "Toilet paper" is the newspaper one read while on the toilet.
24. Even though they are called "Hindu-Arabic numeral system", there are absolutely no evidence of any sort of logic in numbers in Chennai in any context. Example: You get token 33 for waiting your meal, number 8 is called, than number 42 is next, etc...
25. For any job that need to be done and it is necessary N number of people, in Chennai there will be at least N+2 doing it with the efficiency of N/3.
Live or lived in Chennai? Contribute with some more facts in the comments.
* Lots of this also apply to India in general, but, hey, Chennai is the best in EVERYTHING, rightAAANH?