From Formatio Reticularis:
SimThyr is a continuous simulator for pituitary-thyroid homeostasis. Pre-compiled Software is available for Mac OS X, Mac OS Classic and Windows. SimThyr was developed with Lazarus / Free Pascal (Mac OS X and Windows) or THINK Pascal (Mac OS Classic), respectively. Source code is provided for all supported platforms and may also be used in order to compile SimThyr for additional platforms.
What's new in this version: