Size 94kb, downloads 2082.
Renju is "the aristocrat of five-in-a-row games", according to the the late board game expert David Pritchard. It takes the simple concept of five-in-a-row, and turns it into a balanced games by placing some restrictions upon the player who goes first, who otherwise would have the easier win.
This print-and-play file contains the board in six parts, and the pieces, which can be printed out on to sheets of A4 card. The final page contains instructions for assembly and play.