FreeCell Pro (or FC-Pro or FcPro for short) is an enhanced implementation of FreeCell for windows, written by Adrian Ettlinger and Wilson Callan. It was released as open source code under the GNU General Public License (GPL).
FreeCell Pro was heavily inspired from the built-in FreeCell implementation that ships with Microsoft Windows, but greatly improves upon it. Very early versions of FC-Pro shipped with the Don Woods FreeCell solver and the most recent version also integrates Freecell Solver by Shlomi Fish and Patsolve by Tom Holroyd as additional solvers.
FreeCell Pro also has unlimited redo and undo, saved games, an extended number of available deals (up to 8 Milliard), solution recording, and many other features. The demo/auto-play display now runs too quickly on modern computers, due to lack of delays between the moves.