All the answers are given inside this page, but it will require some lateral and/or logical thinking to find them (and no, emailing me isn't the answer)! I recommend you try to answer the questions and if you can't figure out how to find the answers based on my statement above, you can look at another hint.
Most of the answers here require lateral thinking, i.e., thinking outside the box, but some require straight logical and/or mathematical thinking, and in still others, the answers require realising that the questions are misleading.
1. There is a man who lives on the top floor of a very tall building. Everyday he gets the elevator down to the ground floor to leave the building to go to work. Upon returning from work though, he can only travel half way up in the lift and has to walk the rest of the way unless it's raining! Why?
This is probably the best known and most celebrated of all lateral thinking puzzles. It is a true classic. Although there are many possible solutions which fit the initial conditions, only the canonical answer is truly satisfying.
2. A man and his son are in a car accident. The father dies on the scene, but the child is rushed to the hospital. When he arrives the surgeon says, "I can't operate on this boy, he is my son!" How can this be?
3. A man is wearing black. Black shoes, socks, trousers, jumper, gloves and balaclava. He is walking down a black street with all the street lamps off. A black car is coming towards him with its light off but somehow manages to stop in time. How did the driver see the man?
4. One day Kerry celebrated her birthday. Two days later her older twin brother, Terry, celebrated his birthday. How?
5. Why is it better to have round manhole covers than square ones? This is logical rather than lateral, but it is a good puzzle that can be solved by lateral thinking techniques. It is supposedly used by a very well known software company as an interview question for prospective employees.
6. A man went to a party and drank some of the punch. He then left early. Everyone else at the party who drank the punch subsequently died of poisoning. Why did the man not die?
7. A man died and went to Heaven. There were thousands of other people there. They were all naked and all looked as they did at the age of 21. He looked around to see if there was anyone he recognized. He saw a couple and he knew immediately that they were Adam and Eve (from the Bible). How did he know?
8. A woman had two sons who were born on the same hour of the same day of the same year (almost at the same moment). But they were not twins. How could this be so?
9. A man walks into a bar and asks the barman for a glass of water. The barman pulls out a gun and points it at the man. The man says "Thank you" and walks out. Explain.
This puzzle claims to be the best of the genre. It is simple in its statement, absolutely baffling and yet with a completely satisfying solution. Most people struggle very hard to solve this one yet they like the answer when they hear it or have the satisfaction of figuring it out.
10. A man without eyes sees plums on a tree. He neither takes plums nor leaves plums. How can this be?
This is a very special question for me; people who know me personally have already been provided with a huge clue.
11. Jack and Jill are found dead, lying on the floor in the living room of a house, in a puddle of water. How did they die?
12. A man is found dead in an empty field with a pack strapped to his back. How did he die?
13. A man is found hanging in a completely empty warehouse high off the ground. How did the man manage to hang himself.
14. A frog is dead in the centre of a pond, surrounded by ten feet of water on all directions. How can the frog get to land?
15. You have three lights in a box, each of which is connected to a switch outside the box, i.e., one switch one light. The box is closed. You need to figure out which switch to corresponds to which light and you can open the box only once (and you can't manipulate the switches after you open the box). How do you do this?
16. A pot of gold is on a square island surrounded by a chasm 10 metres wide and of infinite depth. You have two 9.8 metre poles. How do you get across to the pot of gold and get back with it.
17. Mel Colly stared through the dirty soot smeared window on the 64th floor of the office tower. Overcome with depression he slid the window open and jumped through it. It was a sheer drop outside the building to the ground. Miraculously after he landed he was completely unhurt. Since there was nothing to cushion his fall or slow his descent, how could he have survived?
18. A man is hiking up a snowy mountain, he comes across a cabin. Inside the cabin is a small fire and two dead men. How did they die? (They did not burn to death.)
19. Three guys walk into a hotel, and they're going to split the cost of a room. The room is $30. They each kick in $10 and head up to their room. The manager gets wind of it and tells the clerk the room is only $25. He hands five $1 bills to the bell hop and tells him to go refund the guys' money. On the way up to the room, the bell hop gets to thinking, as bell hops are wont to do, and says to himself, "No way can three guys split $5, I'm going to help out." He stuffs $2 in his pocket, knocks on the door, gives each guy back a buck and heads back downstairs to the desk, glowing in the warmth of a job well done. So now each guy has paid $9. $9 times 3 is $27 plus $2 the bell hop stole--only $29! Where is the other buck?
20. Please answer yes or no only. Have you stopped beating your spouse yet?