Another classic 3M game from my large box that I bought at GenCon is Ploy.
In Ploy, the object of the game is to capture your opponent's commander, or all of his other pieces. It has a very Chess-like feel. Each of your pieces has 1-4 lines on the top of it. On your turn, you are allowed to move 1-3 spaces (depending on the piece), but only along one of the paths that the piece is pointing towards. Conversely, you may take your turn to re-orient one of your pieces instead. Play consists of taking turns moving a piece either along a line or by re-orienting it until all but one of the players (it can be played two or four player) have lost their commander or all of their pieces other than their commander.
The next thing that I like about Ploy is how the movement works. I think that it is neat. I don't really know how to describe this pro better. Seeing the board and orienting your pieces, then moving them to where they need to go as you try to strike while your opponent's pieces are facing the wrong direction just has a "neat" feel to it.
However, though I think that Ploy is neat, there are definitely some cons. First of all (disclaimer - I don't like Chess), Ploy embodies everything that I hate about Chess. It is a game of positioning and patience. I like thinking in games, but I do not have the patience for constantly protecting each of my pieces as I attack my opponent at a glacier's pace. That is how I feel about Chess, and that feeling is carried into Ploy. If you like Chess, I think that you will actually love this aspect of Ploy, and it may put you on a level footing with your friends - if you enjoy playing Chess with them, but have not studied the game as much as they have. Playing Ploy may be a way of getting a similar feeling game without feeling like someone wins because they've studied the game more.
The last thing that I will mention about Ploy is that it is "fiddly." Since the pieces spin, and do not lock into place, it is very easy to accidentally nudge them and have them facing between two lines with you not knowing which ones they are supposed to be facing. If you are a gamer that constantly need things to be neat - your always stacking discard piles, etc, then you will probably find yourself spending a lot of time in Ploy fidgeting with the pieces on the board trying to make sure that they are always lining straight up with the lines that they point towards.
Overall, I think that each person's enjoyment of Ploy will be directly related to how much they enjoy Chess. Therefore, I give Ploy a 6.5/10. I have debated this quite a bit - I think that Ploy is a very good game. Unfortunately, I also think that it is horribly boring, in the same way that I think that Chess is horribly boring. If you disagree with me on this one crucial point, then you should definitely check out Ploy, because it is a game that you might love!
If you like vintage 3M games, you should also check out my reviews of Acquire, Quinto, and the (non-3M game that might appeal to a similar audience) Ploy.