Once upon a time there was that yellow cowboy riding his yellow horse somewhere in the yellow desert. He was desperately looking for a yellow hotel with a yellow room and a yellow door with a yellow number 3 on it. After 3 yellow days riding his really tired yellow horse, the yellow cowboy finally saw the yellow hotel in the yellow desert. He (the yellow cowboy) entered the yellow door of a yellow hotel, walked right to a receptionist (who was also yellow, btw) and asked: Do you have a yellow room with a yellow door with a yellow number 3 on it? The yellow receptionist answered politely: I’m so sorry, yellow cowboy, but we don’t have any yellow room with a yellow door with a yellow number 3 on it. The yellow cowboy thanked the kind yellow receptionist and started searching for another yellow hotel with a yellow room and a yellow door with a yellow number 3 on it. Then after 2 yellow days the yellow cowboy who was of course riding his yellow horse saw another yellow hotel so he went to a receptionist (yeah, he was yellow too) and asked: Do you have a yellow room with a yellow door with a yellow number 3 on it? The yellow receptionist answered : Nope, we don’t have any yellow room with a yellow door with a yellow number 3 on it. The yellow cowboy thanked the yellow receptionist and then started searching for another yellow hotel with a yellow room and a yellow door with a yellow number 3 on it. Unfortuntely his yellow horse died in the yellow desert so our yellow cowboy had to walk the yellow desert cause he was searching for a yellow hotel with a yellow room and a yellow door with a yellow number 3 on it. Then he saw one more yellow hotel and went to the yellow receptionist and asked: Do you have a yellow room with a yellow door with a yellow number 3 on it? The yellow receptionist answered: Yeah, we do have a yellow room with a yellow door with a yellow number 3 on it. The yellow cowboy then said: Cool! Could you give me a key to a a yellow room with a yellow door with a yellow number 3 on it? The yellow receptionist said: Yes, I’ll give you the key to a yellow room with a yellow door with a yellow number 3 on it, it’s just that the key is YELLOW too. The yellow cowboy said: Good. Could I get the yellow key to a yellow room with a yellow door with a yellow number 3 on it. The yellow receptionist answered: Sure you can get the yellow key to a yellow room with a yellow door with a yellow number 3 on it. The yellow cowboy then took the yellow key to a yellow room with a yellow door with a yellow number 3 on it. He went to a yellow door of a yellow hotel room and there was that yellow number 3 on the door of course. He then opened the yellow door with a yellow key and slowly entered the yellow room where everything was well, yellow of course, except that one little BLACK spot on the yellow wall.
The question is: What was that? 
