Gambatte is an accuracy-focused, cross-platform Game Boy and Game Boy Color emulator. It is based on hundreds of corner case hardware tests, as well as previous documentation and reverse engineering efforts. The core emulation code is contained in a separate library back-end (libgambatte) written in pure platform-independent C++. There is a GUI that uses Trolltech's Qt4 toolkit (gambatte_qt), and a simple command-line SDL front-end (gambatte_sdl). The GUI front-end contains platform-specific extensions for video, sound, and timers.
Tunguska is a computer emulator and virtual machine that uses numerical base three (ternary) number system for its lowest-level operations instead of the commonly used base two (binary) number system. Its goal is to provide a useful experimental platform, on par with early personal computers.
WANsim allows you to simulate (more accurately, emulate) a WAN connection. In particular, it allows a user to change the emulated WAN speed, latency, variation, packet loss, packet duplication, and packet corruption aspects. It is configured as a network bridge that is established at boot time and uses the Linux Kernel NETEM functionality to accomplish its goals. Although relatively well documented, this functionality is not the easiest to use. WANsim wraps it into a simple to use script.