RemObjects Oxidizer is a free command line utility that helps to port Delphi code (both from Win32 and the now deprecated Delphi for .NET) projects to the Delphi Prism language. It does so by analyzing your pascal source files and applying a wide variety of changes, both for subtle language differences but also to prepare your code for more fundamental differences between Delphi Prism and traditional Delphi code.
The goal of Oxidizer is not to generate code that will compile and be perfect .NET code out of the box; Delphi and .NET are two very different platforms and as such, manual review and adjustment will always be needed to get code ported over and behave properly in a .NET world. But Oxidizer will take care of a lot of the grunt work, both things that would take a lot of cumbersome Search and Replace and changes that are more tricky to manually apply because they rely on code context that a plain text editor does not have (such as replacing = with := in default parameters and attribute property assignments, without mangling any other valid uses of the = operator in the process).
Oxidizer itself is a work in process, and we will continue to enhance it over time. Your feedback is essential in doing that, so if you are porting projects from Delphi to Delphi Prism and run into common scenarios not covered by Oxidizer yet, please make sure to let us know, through our regular support channels, so we can expand Oxidizer.
Oxidizer is free, however does not include source as it depends on the Prism compiler code to do it's work.