Knoppix is the only distro that...

[Capricorny]

Basically, there are two ways to get out of the 4GB persistent store squeeze without going into "experimental" features. First, running Knoppix off a Poor Man's Install on a file system allowing >4GB files (NTFS, ext3/4 reiserfs...), and extending the persistent file. This may also be done on a USB stick, creating a smaller boot partition, putting Knoppix on a larger storage partition, and micro-remastering.

In my experience, if 4GB persistent store is really too little, it is in many cases way better to go by the second route: You mount extra volumes, either directly as partitions, or as loop-mounted images. I routinely setup a large storage partition on the main hard disk, mount it on /store, and use it for all sorts of storage except for programs and program data. If I have to use a Windows PC and cannot re-partition the main disk, I set up a large loop file and mount that image as /store.

You can also extend persistent store within the FAT32 limitation by adding volumes knoppix-data2.img, knoppix-data3.img etc in the KNOPPIX directory, and, for example, modify /etc/rc.local to mount them on boot. Those will be copied with the directory when you use the plain old knoppix-to-flash function.