I'm working on a project to replace the physical board and counters from any hex and counter board game with a gosu app.

What I'm most happy with so far is my input handler and widget system. I'm thinking about breaking it out into a library if anyone is interested. The input handler supports drag-drop, double_click, click, mouse_down, mouse_up, mouse_entered, mouse_exited. And the widget system handles drawing and event propagation up and down a graph of parent and child views.

Take a look:
https://github.com/timgaleckas/hex_and_counter_board_game