I saw the lack of a good RomFS Builder as a problem, so I made this thing.
It's very, very simple.
Open a folder using the Open button, then hit Go. The program will then generate a RomFS binary.
When it's done, it'll prompt you to save the binary with a file name of your choice.
Source Code is available here: https://github.com/SciresM/RomFS-Builder
And you can download it here: https://github.com/SciresM/RomFS-Builder/releases

It's very, very simple.
Open a folder using the Open button, then hit Go. The program will then generate a RomFS binary.
When it's done, it'll prompt you to save the binary with a file name of your choice.
Source Code is available here: https://github.com/SciresM/RomFS-Builder
And you can download it here: https://github.com/SciresM/RomFS-Builder/releases