MegaTunix is a cross-platform tuning application for some of the available DIY Fuel Injection controllers, including the MegaSquirt (MS1, MS1-Extra, MS2 and MS2-Extra) as well as the LibreEMS EFI system and the JimStim ECU stimulator/development tool.
EFIgy is a viewer for EFI (electronic fuel injection) log files. It uses plugins to extend its functionality. Current plugins are mostly for the Holley Commander 950.