GradeCam employs the primary developer of FireBreath (Richard) and allows him to work on FireBreath when there aren't fires to put out for them. GradeCam has some really amazing technology that is hosted in a FireBreath plugin that is changing the way that teachers get feedback from students in the classroom.
For about a year Facebook employed Richard (the original author and primary developer) to work on some internal plugin work for them and contributed significantly to the growth of FireBreath as a project.
Mogotest is a great new service for Web developers that can detect cross-browser render differences on multiple browsers and operating systems. It utilizes a FireBreath plugin behind the scenes! Mogotest has assisted with the FireBreath project by providing testing, suggestions, and development tools for the core developers.