Comment 8 for bug 237575

Well, FAT is what most USB sticks come pre-formatted as, as far as I'm aware. So the filename restrictions are a problem that a lot of people are going to face, and not one that we can do much about in Ubuntu.

If you want to back up an entire system, I suggest you put the files into some sort of archive, and give that a dull, boring name that works anywhere. A Zip archive is good for cross-platform, or a Gzipped Tar archive is a more traditional Unix-ey solution.

While I agree that 4GiB maximum file size (note that that's for one file, not a whole disk) might be starting to limit some people, nothing springs to mind that would normally exceed that limit (Ubuntu DVD images are about 3.3 GiB). I suspect that before files of that size become common, the standard for USB sticks will have changed--probably to NTFS.

You can of course format your stick as NTFS already--that supports extended filenames, and will work with modern Linux and Windows. I don't know about Macs.

If you do want to set up the ext3 based system you described, then you will need to make a small FAT (or NTFS) partition on your USB drive, and place in there the installer for the Windows ext IFS driver, which can be found at http://www.fs-driver.org/