A good verbal game to hone your math skills and blow your mind.

1. All players agree on a one-digit number. This is usually something from 3 to 8.
2. One player starts at one.
3. In sequence, each player names the next number.
4. If the number to be named is either
   • A multiple of the chosen number
   • A number that contains the chosen number in its notation
   That player says 'buzz' instead of the given number.
5. If a player fails to say 'buzz', or says 'buzz' inappropriately, they drop out. If a player hesitates too long, they drop out. Whenever a player drops out, the game restarts.
6. The last man standing wins.

Example

the number is '4'

1. 1
2. 2
3. 3
4. buzz
5. 5
6. 6
7. 7
8. buzz
9. 9
10. 10
11. 11
12. buzz
13. 13
14. buzz
15. 15
16. buzz
17. ...

It's usually very difficult to keep track of both what your number relates to the given number, and whether it is a multiple or not. The best strategy is to think ahead to the number you need to say as the other players are struggling with their own numbers. This usually gets hairy when you enter the range of 10*(chosen number), and you have to keep track of the unspoken numbers through a hail of buzzes.