Downloading MacIsing 1.1 for Mac from our website was free. This free Mac app was originally developed by Fabio Cavaliere. The software relates to Design & Photo Tools.
From the developer:
MacIsing is a freeware interactive Montecarlo simulation of the 2D Ising model on a square lattice. Nearest-neighbours and next-to-nearest neighbours interactions are considered and different configurations including interface between para- and ferromagnetic materials can be simulated. The simulation speed and the grid size (up to 600x600 spins) can be customized by the user.
You may want to check out more Mac applications, such as FRS Coloring Book Volume 2, FbxConverter or JMRI, which might be similar to MacIsing.