The Data Display Debugger (DDD) is a popular graphical user interface to UNIX debuggers such as GDB, DBX, XDB, JDB and others. Besides typical front-end features such as viewing source texts and breakpoints, DDD provides an interactive graphical data display, where data structures are displayed as graphs. Using DDD, you can reason about your application by watching its data, not just by viewing it execute lines of source code.

A graphical program that tracks how your time is spent. Maintains a simple list of tasks, each of which can belong to a project, and allows you to track time in each. Multiple clocks can run simultaneously, annotations can be added to a day's time, and reports can be generated in either HTML or text. If GTimer detects that you're idle, you are given the option of subtracting off the time you spent idle when you return.

4digits is a guess-the-number puzzle game. It's called Bulls and Cows, and in China people simply call it Guess-the-Number. The game's objective is to guess a four-digit number in 8 tries and the shortest time possible. It is similar to Mastermind, but the four digits must be unique. 4digits has both a graphical user interface version and a command-line version.

DiffPDF is used to compare two PDF files. By default the comparison is of the text on each pair of pages, but comparing the appearance of pages is also supported (for example, if a diagram is changed or a paragraph reformatted). It is also possible to compare particular pages or page ranges. For example, if there are two versions of a PDF file, one with pages 1-12 and the other with pages 1-13 because of an extra page having been added as page 4, they can be compared by specifying two page ranges, 1-12 for the first and 1-3, 5-13 for the second. This will make DiffPDF compare pages in the pairs (1, 1), (2, 2), (3, 3), (4, 5), (5, 6), and so on, to (12, 13).

A card game against the computer in which each player tries to reach 1000 miles. Each player tries to avoid accidents, flat tires, running out of gas, and break downs while trying to cause these same maladies in the opponent.