PipeNightDreams is a game similar to the classic PipeDreams that runs under X11. It is implemented using the SDL libraries. It has 25 levels with increasing difficulty, and you can create your own by editing the text files. It has a lot of cool graphics, and a simple and fast interface.
Cryptogram Puzzle Tool helps solve the simple cryptogram puzzles that appear in the daily newspapers. While these puzzles can often be solved almost by inspection, CPT4 provides a handy tool the ones that turn out to be not quite so easy. If you just want a little bookkeeping help, CPT4 will instantly update all occurances of the new assignments as well as provide frequency and used/not-used letter lists as you drag-and-drop or key in suspected solution letters. But if you'd rather have the computer do the work, the automatic solution algorithm will usually come very close to a complete solution in just a few seconds. CPT4 can also create new puzzles from keyed in plaintext or from a file.