GPL-It

GPL-It is a free and open-source application that facilitates a user-friendly interface for adding GPL or other types of copyright notices to your source files.

Prerequisites and interface

It's not wrapped in a setup package, so you can save the downloaded files to a custom location on the disk or copy them to a USB flash drive, in order to run the tool on any machine.
However, .NET Framework must be installed. It doesn't modify your system registry settings or create files on the disk without asking for your permission.
When it comes to the interface, GPL-It adopts a standard .NET Framework form and keeps all options neatly organized.

Set project details to generate copyright notices

After indicating your project's root directory, you can create a list with extensions to add, load existing headers from plain text documents, as well as copy and save headers.
Notices can be generated by entering the project's name, description, author and year. There's also a template available but you can change any parts of it, as well as insert tags with the previously mentioned project properties. Any text can be selected and copied to the Clipboard. There are no other notable options available here.

Evaluation and conclusion

We haven't come across any stability issues in our tests, thanks to the fact that the program didn't freeze, crash or indicate error messages. It left a small footprint on the overall performance of the computer, since it needed a low amount of CPU and memory to work properly.
On the other hand, GPL-It is an unpolished software application that hasn't been updated for a long time. Nevertheless, it gets the job done and you can test it for yourself, since it's free and open-source.