Okay i've made a list over 10 things what you maybe didn't noticed in the movie. A lot of them are small hints to Tyler & the narrator being the same person. I've tried to find a video to each thing. But couldn't
Please comment, and vote in this pick :

link

- Enjoy, Homa.

1. When Lou punched Tyler in the stomach, you can see the Narrator double over slightly as if he was punched too.

Video:link

look at around 4:36-4:38.

2. In the bus where a man walks in to Tyler & The narrator, he first says excuse me when he walks in to THE NARRATOR?

video:link

look at around 0.50-0.55.

3. In the scene where The Narrator, Tyler Durden & the space monkeys go for a ride, the chauffeur talks to Tyler - but looks at the Narrator. The Narrator then looks at Tyler and says "After you Mr. Durden", Tyler answers "No after you."

Video: link
look at around 4:20 - 4:30

4. In the beging of the movie there are 4 Tyler flashes. He apears in small seconds, and then dissapears again. This is before Tyler & the narrator have meet.

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link
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link


5. In the ending of the movie when the buildings are crashing the song "where is my mind" is playing, at the very end there is a flash of a penis. This is Tylers work, or you know .. The narrators ..

link

Look at around 3:40

6. When Tyler is about to tell the Narrator about how he met Marla, the Narrator says "I already knew the story before he told it to me."

7. This is VERY hard to see, but if you look closly you can see it. When the Narrator returns to the Paper Street house after Project Mayhem sets fire to the building and paints the smiley face, you can see green paint on the Narrator's hands and sleeves.

found a picture, but you can't see it so much:

link
link

EXTRA: look at this picture: link

The Narrator is holding one of the Project Mayhem folders

8. When the narrator gets on the bus with Tyler, he only buys a ticket for one.

9. I couldn't find a video for this but, in the beginning of the film, the Narrator can be seen as Tyler's reflection in the window in a short moment.

10. Marla & Tyler:
The Narrator walks around in the house while Tyler and Marla noisily have sex upstairs. When the detective calls and the Narrator answers the phone, the sounds of the lovemaking instantly stop.

When the Narrator passes Tyler's room when he and Marla are having sex, Tyler opens the door to talk to the Narrator. When they stop talking Marla says "who are you talking to you" and Tyler tells her to shut up.