To quote from his site (linked above): FreeFlash is a PS3 application that creates a new and writable flash device FreeFlash. The original "dev_flash" device is kept to avoid issues.
We do NOT take any responsibilities for the wrong use of this application.
Requires payload with "peek" and "poke" syscalls. No version spoofing.
Finally, for those curious, http://www.teknoconsolas.es/blog/waninkoko/ps3mlib-ps3-multilib is a high-level library designed to allow the creation of homebrew applications for the PS3, in a simple way. PS3mlib is developed to work with the SDK PSL1GHT.