FreeNono is an open-source implementation of the Nonogram game — a logic puzzle in which cells in a grid have to be colored or left blank according to numbers given at the side of the grid to reveal a hidden picture.
FreeNono is distributed under the terms of the GNU GPL.
An excellent game with a good selection of built-in puzzles and several gameplay modes. Some aspects of the user interface could use a bit of work: 1. The various text colors should be configurable independently of the "base" color. Currently, they're determined by the base, but this can result in some of the text being extremely hard to read. 2. The puzzle should automatically resize when the window does. Currently, you have to restart the puzzle to get it to resize. 3. There needs to be an option to scale large puzzles instead of adding scroll bars.