Hey all, I have a copy of my Install Mac OS X Lion.app saved on a thumb drive, just in case I ever want to perform a clean install, or access any of the files inside with the handy program Pacifist. However, a 4.2GB file is somewhat burdensome on my USB drive, so I wanted to know if there was a way I could compress the .app to save space. I have used Keka, which is a very nice freeware compress and uncompress utility for OSX, but even when I set the compression setting to maximum, the file only shrinks by about 100MB. I've tried using both 7z and zip formats, but neither seems to work very well. Is there an app, format, or method that I could use instead that would allow me to compress the install app to a more reasonable size? I could see myself using an archive utility to break the file into multiple .rar archives, but that wouldn't be an optimal solution. Could I put the .app inside of a compressed .img via Disk Utility? Any suggestions would be most appreciated!