It is possible to dump PS3 Blu-Ray images to iSO files via a Linux install. If you have a 60GB HDD PS3, you may dump images directly via the following command:
Code:
dd if=/dev/cdrom of=/imagename.img
That said, the file structure of PS3 games is said to be similar of thsoe on the PSP. A dump of Madden 07 reveals the game is just over 7GB in size.

A complete and detailed guide on this process is available at http://PS3.PS3News.com!