I just got my new computer with a much bigger harddisk. I think I copied all important files over but just to be sure, I'd like to keep a disk image of my old disk. To save space, I'd like to compress it but I didn't find an option to mount a compressed image.

My goals:

• Result must be easy to access
• No need to decompress the whole thing before I can access anything
• Files should be quick to locate - no TAR/CPIO archive
• Necessary space should be less than just copying the files over

So ideally, I'm looking for a read-only, compressed file system which I can create in a file and which grows automatically.