Wine - Open Source Software for running Windows applications on other operating systems.
CodeWeavers CrossOver - Don't buy a Windows license, don't reboot and don't use a Virtual Machine. Try a free trial of CrossOver to run your Windows software on Mac, Linux and Chrome OS.
Cautoh - Turn your phone into a breathalyzer
WineBottler - WineBottler is an App to manage and wrap your Windows apps into convenient OS X apps.
Truck - A faster alternative to FTP
Proton - Compatibility tool for Steam Play based on Wine and additional components