Plash is a sandbox for running GNU/Linux programs with minimum privileges. It is suitable for running both command line and GUI programs. It can dynamically grant Gtk-based GUI applications access rights to individual files that you want to open or edit. This happens transparently through the Open/Save file chooser dialog box, by replacing GtkFileChooserDialog. Plash virtualizes the file namespace and provides per-process/per-sandbox namespaces. It can grant processes read-only or read-write access to specific files and directories, mapped at any point in the filesystem namespace. It does not require modifications to the Linux kernel.
MT-write is a binary patch for multi-threaded writing. It comes in the form of a shared object that can be preloaded to programs like tar to make their write operations multi-threaded. Multi-threaded writing can improve performance on RAM based filesystems and highly scalable filesystems with multiple spindles.