The Alesalitis Plant 

Copyright (c) 2003 Tim Schutz

This game is played on a 4x4 square board:

SETUP - One player drops four (black or white) stones not orthogonally adjacent to each other. The other player decides who starts.
TURNS - On each turn, each player drops a stone of either color on an empty cell orthogonally adjacent to at least another stone.
All stones orthogonally adjacent to that stone, flips color (black turns white, white turns black).
Harvesting - After the flips, any four in-a-row (with stones of the same color) is removed from board, and that player gets one point. 
A move may produce more than one four in-a-row, but they cannot share stones (if two or more share stones, the player removes just one of them).
The first player harvesting a black four in-a-row, gets a special point. This point is given to the adversary when he creates a black four in-a-row.
When a player does not have a valid more, the game ends.
GOAL - The game ends when either (a) there are no empty cells, (b) the board is empty, or (c) the number of points of both players (not including the special point) plus the number of stones on the board is equal to twenty. 
Wins the player with more points (this score should include the special point for the player that achieved the last black four in-a-row). 
If the points are equal, second player wins.

If you use Reversi stones to play this game, condition (c) from endgame can be simplified: for each four in-a-row, keep one piece and return the other three to the common pool. When there are no more pieces to drop, condition (c) is true.

An example

The current player dropped a white stone at [1].


He made two four in-a-rows, but they share a stone (the marked stone at c2). So, the player must select only one of those to remove, earning one point.

This game entered at the 2004 Shared Pieces Game Design Competition and was considered among the best entries.