The Game Dump Extractor incl. source code was released by Team PI Coder. It allows you to extract Xbox360-ISO image files (x360dvdfs). Just like the original Xbox (xdvdfs) the 360 does not use the ISO9660 or UDF filesystem for the content on game DVDs. This tools allows you to extract the files from an image in the 'Xbox 360 DVD file system' (.360). As there seems to be some kinda confusion about this: it does NOT bypass the protection that prevents you from reading an original Xbox 360 disc on your PC, so you can't use it to access/read original Xbox360 discs.
Download Halobox GUI Game Dump Extractor: here
Download Sonia GUI Game Dump Extractor: here