Game Courier supports many different games. Here is one picked at random: Secutor Chess - The Secutor is a bifurcation piece that must collide and deviate in order to capture (+zrf).
Abstract Chess. Pieces are really by stacks of stones of different heights, with their move depending on the number of stones. (8x8, Cells: 64) Author: Peter Aronson. Inventor: João Pedro Neto.