Polarity has to be one of the most unique abstract strategy games ever invented. It's primarily a two player game but the rules can easily be adapted for four players playing as teams. Games typically last around ten minutes.
Polarity is played on a canvas playing mat marked with a circular playing area roughly twenty inches in diameter. Each of the plastic pieces is actually a magnet, colored black on one side and white on the other. All of the pieces pack neatly in a cardboard tube which, when rolled up inside the playing mat, slips inside a lovely canvas carrying bag with a leather tie. The production quality is first rate.
At the start of the game, players choose sides by flipping a red magnet marked with a bar or dot which is then placed in the center of the playing area. White goes first and places five of his disks, white side up, on the playing surface then Black does the same (black side up of course). These ten disks are called "foundations" and become the base upon which the rest of the game is played. From that point on, all pieces must be played in such a way that they lean (or float) against the magnetic field of one or more foundation pieces. This gives the game a rather eerie quality as pieces seem to delicately hover and float about the playing surface.
As new pieces are placed, the magnetic fields combine and alter, pieces waver and bob, and eventually something will become unstable and pieces will fly towards one another. When this happens, the player is said to have "faulted" and the opposing player gets to attempt to recover the faulted pieces, converting them into towers of her own color.
The game ends when one player has successfully played all of her pieces. At that point, players count up all the pieces in their towers and subtract any pieces in their hands to arrive at their scores.
Polarity is simple to learn, challenging to play, and elegant in its design. Win or lose, it's absolutely delightful to watch the pieces hover and bob as if by magic. It's addicting and very unique. I consider this a must have game for abstract game lovers and science geeks alike.