On the wiki:
Also, tcllib includes the normal, exponential, and uniform distributions.
Typical functionality in tcllib includes:
GNU MCSim is a simulation package, written in C, which allows you to design your own statistical or simulation models, perform Monte Carlo stochastic simulations, and do Bayesian inference through Markov Chain Monte Carlo simulations.
It includes a GUI program, XMCSim, a menu-driven interface which automatizes the compilation and running tasks of MCSim. It also offers a convenient interface to 2-D and 3-D plotting of the simulation results via gnuplot.