Since this is aasuch a great site to get answers, I was just wondering, if any, what program is used to convert PSP (not PS1) ISO's and CSO's to PBP (EBOOT)? I'm only asking because I recently, bought a used PSP, which came with a 1GB memory stick that had about 15 psp games already installed in it, and still have at least 400MB of free space. How is this possible??? Example---> **Syphon Filter: Dark Mirrior-23.1MB**Bounty Hunters-8.12MB**Metal of Honor : Heros-26.8MB** and so on. The PSP games had the PBP extension. The game size were as small as 70MB to 8,000k. I'm really confused!? I used the program "CSO-DAX Compressor" and used level 9 to compress the smallest size UMD game that I have and it turned up to be a minimum of 200MB. That's still alot. My PS1 games are around the same size also (after compressed). The PSP was previously running firmware 3.10 OE-A, then I upgraded to firmware 3.52 m33-4 (I don't know if the firmware plays a role in the size of the game). Also, is there any other program, besides ImpalerPopStation, that will combine two or more PS1 disc into one image file? Last but not least is it possible to compress a game and then compressing it even further to make the file smaller? Well, if anyone has answers please let me know. Thanks in advance.