WTides is a free program that uses harmonics data to predict tide heights at many locations throughout the World, and displays a graph of the results according to the time zone of the target location.  It runs on any version of Microsoft Windows from Windows 2000.
The tide graph can be overlaid with a solunar chart to give an interesting version of the Maori Fishing Calendar.
WTides is an enhanced port to Windows of David Flater's Unix program XTide. For information about the original program, follow this link.
WTides is free software.  There is no charge for downloading, using or distributing it, and it contains no advertising.  On the other hand, this website costs a little money each month, and a donation to help cover costs is always welcome.
You may download the installation program and/or source code from here.