k10ctl is a P-State utility for AMD family 10h (aka K10) processors. It can modify the P-States, i.e. alter processor and the northbridge frequencies and voltages, set or change the P-State, and read out frequency and voltage information. The main purpose of k10ctl is overclocking or "undervolting" the CPU and to configure Cool'n'Quiet settings.
c2ctl is a frequency and voltage modification utility mainly intended for Intel Core 2 and Core CPUs. It should also work for other CPUs (namely processors with SpeedStep). The utility can also enable SpeedStep (e.g. if it was disabled by the BIOS due to overclocking) and read out frequency and voltage information. The main purpose of c2ctl is overclocking or "undervolting" and to enable SpeedStep.
libcpu is a library that emulates several CPU architectures, allowing itself to be used as the CPU core for different kinds of emulator projects. It uses its own frontends for the different CPU types, and uses LLVM for the backend. libcpu should be able to do user mode and system emulation, and dynamic as well as static recompilation.
SoCLib is a library of pluggable SystemC cycle-accurate and transaction-level components. The library contains many types of models: processor cores (MIPS32, PPC405, ARM-v6k, Nios2, MicroBlaze, lm32, etc.), memory types, devices (block device, UART, frame buffer, etc.) and network-on-chip models. SoCLib can be used to create a complete system-on-chip hardware design, as well as for testing and evaluating embedded operating systems and applications. NetBSD, MutekH, and other dedicated systems are ported to the SoCLib hardware simulator. A Linux port is an ongoing project.
jCores is a Java library that feels like jQuery, with many shortcuts and transparent parallelism. It was made to denoise programming in the Java language and to increase execution speed. Its goal is to demonstrate that Java, the language, can be as sexy as Python in terms of hacking and as parallel as your hardware gets in terms of CPUs.