Puzzling problems

[reanjr]

Looking to collect some puzzle ideas. Anyone have any good puzzles they've used lately? My personal preference is for puzzles that the players have to have a hand in figuring out, but that can be altered or helped by character skill checks or magic.

Example (anachronistic, but serves my point - note, I don't really like this puzzle for D&D as it makes little sense in any but the most specific types of situations)

Sudoku style puzzle. Players need to do the puzzle themselves, but character Int checks can automatically fill in squares.

Puzzle

1  2  _  _
_  _  _  2
_  _  4  _
_  1  _  _

Solution:

1  2  3  4
3  4  1  2
2  3  4  1
4  1  2  3

Puzzle starts blank. Each successful Int check DC 10 fills in a square (+1 square for every 5 points the checks was exceeded by). So a party of 4 might roll 8, 12, 13, and 17 for 4 successes. Puzzle now looks like:

1  2  3  _
_  4  _  2
2  _  4  _
4  1  _  _

Anyway, looking for more ideas.