What two things can you never eat for breakfast?
Find the next number in the series. 1 10 24 43 67 ?
Can you find the key in the picture below?
A girl has as many brothers as sisters, but each brother has only half as many brothers as sisters. How many brothers and sisters are there in the family?
Can you discover the missing number in this series? 37, 10, 82 29, 11, 47 96, 15, 87 42, ?, 15
There are are five things wrong with this sentence; only geniuses will be able to to spot all of the mitstakes
Can you identify the Oscar-winning movie from the rebus below?
You may enter, but you may not come in. I have space, but no room. I have keys, but open no lock. What am I?
What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?
If you remove one from eleven, it becomes ten. If you remove one from nine, it becomes ten. How is this possible?
Two batsman each on 94 runs. Seven runs needed to win in last 3 balls. Both make 100*. How?
There is a cryptic organization called Cicada 3301 that posts challenging puzzles online, possibly to recruit codebreakers and linguists.