Tonight I was in the mood to compress some of my Sony PSP ISOs. I needed an app to do so, and after a little Google-Fu I found a few to do the job. Most were console and all were source releases. I was looking for a .deb package and a GUI. No love in most of my searches but I did happen upon PSPShrink. I couldn't find a .deb of it BUT it did have a GUI + console binaries. The source release was fine with me, I don't mind compiling up some software. After compiling I also whipped up a .deb package for Ubuntu 14.04lts. My PSPShrink .deb might also work on 14.10 but I can't test it after switching back to the 14.04lts release.
Download - PSPShrink 1.1.1 .deb package from Google drive