I've posted this one at Yahoo's club pente and also let Dweebo and Fencer know about it and have shown it to Gary also- still no luck in playing it on the web yet- the difference between pro pente and this one is that a player can in effect create a pre-emptive capture at a given point by placing stones on either side of that point and an adjacent point occupied by an opponent's stone, so in the example X_OX in standard rules O can play at _, but with this rule if O wants to play in that space s/he sacrifices a pair of stones (or possibly more if a stone placed in that spot forms pairs which are captured in several different directions) to the opponent and it then becomes the opponent's move. This can occasionally be a worthwhile sacrifice. A win in this version is 10 stones or 5 in a row. A five must exist at the beginning of the opponent's turn in order to count as a win, so a fifth stone placed into a capture point does not count as a win, as it leaves the board (or never quite lands) before it becomes the opponent's turn. This variant gives the player who is on the defensive more options on defense. For example:
_X
X_XXX
_O
in the figure above O must play into a capture in standard rules, but has the option of playing above the top X in this version. However, in the example
X_XXX
_O
_X
the player O must still play into a capture. It is a very fun variant and I hope to be able to play it online soon!