Joaquim is a java implementation of brazilian checkers (aka draughts) game. It has a console-based interface. Brazilian Checkers has the same rules as International Checkers but it is played on a 8x8 board.
JAM is a popular messagebase format for storing Fidonet messages originally devised by Joaquim Homrighausen, Andrew Milner, Mats Birch and Mats Wallin. JAMLIB is a subroutine library for manipulating such messagebases.