There's a very common game in Russia. We call it Balda. I wasted so many time on it when I was at school :)
Here's the rules:
- there's 5x5 field and the word in the centre
- the players add one character in turn on purpose to form new word. The new word must be formed by iteration through adjacent fields(not by diagonal)
- each character in the word is a point
- only nouns are allowed

Generally it intend for two players but may be we try to play all together :)

For example:

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| _ | _ | _ | _ | _ |
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| _ | _ | _ | _ | _ |
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| t | a | b | l | e |
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| _ | _ | _ | _ | _ |
-------------------
| _ | _ | _ | _ | _ |
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