fat_imgen
fat_imgen is a utility you can use to create and modify FAT12 floppy images with. It is licensed under the GPL v3.
Binaries
For Windows users, the latest stable binaries can be downloaded from the Ohloh project page.
Current Release
The latest stable source code can be downloaded from the latest_stable branch.
Source Code
The latest source code (not guaranteed to work) can be downloaded from the SVN repository. The source code shows many aspects of working with FAT12 images.
Usage
Usage: fat_imgen MODE IMAGE [-b file] [-f file] Main operation mode: create IMAGE Create an image. modify IMAGE Modify an image. File selection: -b File to use as boot sector. -f File to copy onto the image.