Valgrind is a tool that helps you find memory management problems in programs. When a program is run under Valgrind's supervision, all reads and writes of memory are checked, and calls to malloc/new/free/delete are intercepted. As a result, Valgrind can detect problems such as use of uninitialized memory, reading/writing of memory after it has been freed, reading/writing off the end of malloced blocks, reading/writing inappropriate areas on the stack, memory leaks in which pointers to malloced blocks are lost forever, passing of uninitialized and/or unaddressable memory to system calls, and mismatched use of malloc/new/new  vs. free/delete/delete .
StoryText (formerly PyUseCase) is an unconventional GUI testing tool written in Python. It currently has mature support for PyGTK, beta status support for Java Swing, SWT/Eclipse RCP, and Tkinter, and very basic support for wxPython. Instead of recording GUI mechanics directly, it asks the user for descriptive names and hence builds up a "domain language" along with a "UI map file" that translates it into the current GUI layout. Instead of an "assertion" mechanism, it auto-generates a log of the GUI appearance and changes to it, so as to use that as a baseline for text-based testing, using e.g. TextTest. Instead of requiring the tester to add "wait" statements by hand, it includes support for instrumenting code so that "waits" can be recorded.
Scapy is a powerful interactive packet manipulation tool, packet generator, network scanner, network discovery tool, and packet sniffer. It provides classes to interactively create packets or sets of packets, manipulate them, send them over the wire, sniff other packets from the wire, match answers and replies, and more. Interaction is provided by the Python interpreter, so Python programming structures can be used (such as variables, loops, and functions). Report modules are possible and easy to make. It is intended to do about the same things as ttlscan, nmap, hping, queso, p0f, xprobe, arping, arp-sk, arpspoof, firewalk, irpas, tethereal, tcpdump, etc.
CMake is a cross-platform, open-source build system. It is used to control the software compilation process using simple platform and compiler independent configuration files. It generates native makefiles and workspaces that can be used in the compiler environment of your choice. CMake is quite sophisticated: it is possible to support complex environments requiring system configuration, pre-processor generation, and code generation.
DOMjudge is an automated judgement system to run programming contests. It provides a mechanism to submit problem solutions and interfaces for teams, the jury, and the general public. It is lightweight, and depends on standard software to do its task. It has a Web interface for portability and simplicity. It is scalable, so distributed judging is easy. There is a modular system for plugging in languages and compilers. It features rejudging, clarifications, and detailed submission/judging info.
Record Editor is a data file editor for CSV (Comma/Tab delimited values) files, fixed field width files, and XML files. This program uses a record-layout definition to display the data file in a human-readable form. It can handle PC (text and binary), Unix (text and binary), and native IBM mainframe (text and binary) file formats. It is similar to Net-Cobol's Cobol-Editor or Compuware's FileAid.