ProFS
From Just Solve the File Format Problem
ProFS (Preloading read-only File System) by KeyJ (Martin Fiedler) is a proof-of-concept filesystem for Live CDs/DVDs written with Python and FUSE
Instead of waiting for the entire CD to be read into memory, allows immediate access to the files that have already been read. Allows ordering of files so most-likely to be used files are loaded first. If it tries to access a file that hasn't been loaded, the user will have to wait until it has been loaded normally (no seeking).