The dyncall library project provides a clean and portable C interface to dynamically issue foreign function calls using small call kernels written in assembly. Instead of providing code for every bridged function call, which unnecessarily results in code bloat, only a modest number of instructions are used to invoke all calls.
Concurrency Kit provides a plethora of concurrency primitives and lock-less and lock-free data structures designed to aid in the design and implementation of high performance scalable concurrent systems. It was designed to minimize dependencies on operating system-specific interfaces, and most of the interface relies only on a strict subset of the standard library and more popular compiler extensions.
Dynace is a portable extension to the C language which adds object-oriented facilities, including classes with multiple-inheritance, a meta-object protocol, dynamic dispatching via generic functions, a garbage collector, threads, and an extensive class library, including an optional GUI library. It has complete documentation and a tutorial.
The OpenCA OCSP Responder is an RFC 2560 compliant OCSPD responder. It can be used to verify the status of a certificate using OCSP clients (such as Mozilla/Netscape7). The Responder is actually included in the main OpenCA distribution package. It is also possible to install the daemon as a stand-alone application, in which case you will need a CRL (or access to an LDAP server where the CRL can be obtained).