The riddle Randall Munroe (of xkcd fame) has, a bit hidden on his site, a logic puzzle: A group of people with assorted eye colors live on an island. They are all perfect logicians -- if a conclusion can be logically deduced, they will do it instantly. No one knows the color of their eye...

Quivering am i, no mortal halts me, thus no words destroy me. Can you tell me what i am?

My suffix is united. My prefix is full. My infix is united. I am pretty full.

For children, I am a game. For teens, I am reference. For adults, I am a price. What am I?

Across 7. Fly comes flying around place near North Carolina, showing certain smugness (4-11) 9. ISIS fighters maybe capture one town's leader and, among others, foremost loyal people holding on to land rights (15) 10. Pharmacy can offend extremists... and may finally send help to sister's diseas...

Note: This is the second try at asking something that has not yet been answered by the excellent answers to the Oracle question or the skip-ahead question. In this answer to my previous attempt at asking this question, there is an expansion of the tower of hypotheses that slowly collapses — one...

1 + 1 =0 2 + 6 =8 3 + 1 =3 4 + 5 =9 5 + 5 =5 6 + 0 =8 7 + 8 =8 8 - 1 =E

- perform handshake - install es on both ends - pause process in exce - swap chang.exe - combine previous and modify - terminate communication

Here are 5 matchsticks. You should rearrange them, to make nothing But you should not waste or get other matchsticks

There is a number-game which you play like this: You think of a number eg. $8$. Then think: How many letters does this number have? In our example: $5$ And now do step one with $5$ This goes on recursively till you end up with a number which has the same amount of letters as it's value. And tha...

I have the following binary message: 01100101 00101100 01100011 00101100 01101110 01100110 00101100 01100100 00101100 01100100 00101100 01000011 01111000 01100100 00101100 01001110 01111000 01100100 00101100 01101110 01100110 00101100 01101110 01100011 00101100 01100111 00101100 01100010 01100101...

A "Marching Bands" puzzle has rules and a structure that are distinct from a typical crossword: Rows 1-12 each have two answers, A and B. They can be any length (except rows 6 and 7 which are 5 letters each). Circles A-E start in the cell with the letter (top-left of the circle) and move around ...

The answer to this puzzle is a list of ten thematically related words or proper names or phrases. Each of these is clued cryptically, and the theme is to be determined. In this puzzle, the clues are in a specific order which also relates to the theme. Since the definition part of a cryptic clue w...

We call a convex polyhedron a sandpile if one of the faces, called base, has a common edge with all the other faces. Furthermore, each vertex is linked with three edges. We consider the sandpiles by vertex translations, rotations and symmetries close. Therefore, there are 3 sandpiles with a hexag...

It's not everyday you get a text from a dead friend, especially if you saw them being executed by guillotine, which is why D.S.I North Daniels was a bit sceptical when his ancient Nokia Cityman 1320 recieved a text (ding!) from Jane Stephen's number. Double-checking proved that it was the real de...

Since this is a torus maze, the left side of the maze connects to the right side and the top of the maze connects to the bottom. Corresponding openings in the walls of the maze have been labeled for your convenience. Your goal is to get from the start (top left) to the finish (bottom right). Be ...

You have woken up to find yourself trapped in what appears to be a giant Rubik's cube. A Rubik's Cage I suppose. Bewildered, you take a look around (better video on imgur). Each of the individual cube faces seems to have a letter transcribed onto it from outside, although it is difficult to read...

Here is a variation of the hat-guessing logicians problem. 100 logicians are given hats. They know that: All the hats are either black or while Each hat may or may not have green stripes on it Each hat may or may not have a pompom on top At least one of them will be wearing a black hat with gree...