pingspray is a tool that generates network traffic for EMC (electromagnetic compatibility) tests. It can generate both random and periodic patterns of data as suggested in some EMC standards. It uses ICMP echo requests (ping) to generate traffic, and when it works as intended, it will generate traffic in both directions.
timeplotters is a collection of command line tools for visualizing temporal data. It is especially useful for visualizing data from ad-hoc program logs, helping you to spot patterns and anomalies that you would not otherwise see by just watching how the program works or by looking at the logs with the naked eye. Its input format is tailored to event types typically seen in program logs, and the visualization methods are tailored to the questions typically asked about program performance (e.g. distribution of activity durations).
Libtrading is a C library for trading securities, foreign exchange, and financial derivatives electronically. It implements market data, order entry, drop copy, and related communications protocols used by exchanges and alternative trading venues across the world. The library is designed for high performance and robustness. Although latency is very important in trading today's markets, achieving it it must not jeopardize trading reliability.