envbot is an advanced modular IRC bot coded in bash. Features include SSL, IPv6, modularity (with several good modules already), transport modules (including OpenSSL, GnuTLS, netcat, etc.), loading/unloading/reloading of modules at runtime, rehashing configuration at runtime, advanced access control, and much more.
jrMandel is a command line, parallel Mandelbrot set fractal renderer. It is specially designed to render high-resolution fractal images taking advantage of parallel processing, either by using multiple threads of execution (and thus suitable to run on multi-core processors) or by using a Parallel Virtual Machine (PVM) to distribute the tasks among the nodes of a computer cluster. jrMandel can also render fractals without using any parallelism, in order to compare the efficiency between parallel and non-parallel runs.