MoNKey is an m,n,k-board game in which two or more players take turns in placing a stone of their color on an m×n board, the winner being the player who first gets k stones of their own color in a row, horizontally, vertically, or diagonally. Thus, tic-tac-toe is the 3,3,3-game and free-style gomoku is the 19,19,5-game.
Playing MoNKey is easy! Select a game type. Currently there are the following choices: "Tic-tac-toe", "Free-style gomoku", "Four players" and "Connect6". Then hit "Create game". This brings up a Go-like board and you'll need to wait for the remaining players to join the game. If this takes too long, you can hit "Add CPU player" to fill up the empty spot(s) with robots. Now you ready to play and as soon as it is your turn, you can place a stone on the board. At any time you can go back to the lobby to see if you like to join/view some other game or abandon the game at all. A fun thing is also to watch a "CPU battle". You can hit "log in" to authenticate yourself using your Google account or any other openID credential. You can also just hit "Anonymous" and change is to some other name.
MoNKey was developed originally by Andreas Blixt and is released under apache license (source code). MooTools is released under the Open Source MIT license, which gives you the possibility to use it and modify it in every circumstance.