FSlint is a toolkit to find various forms of lint on a filesystem. At the moment it reports duplicate files, bad symbolic links, troublesome file names, empty directories, non stripped executables, temporary files, duplicate/conflicting (binary) names, and unused ext2 directory blocks.
Laptop Mode Tools allows you to control various power management settings based on AC/battery power state. Among other things, it controls Linux's "Laptop Mode" feature that allows your hard drive to spin down for extended periods. It can also control CPU frequency scaling and screen blanking timeouts (both terminal and X). It supports automatic hibernation when battery is low.
muser lists processes which have a given directory (or cwd if not specified) as a parent of their current working directory (thus making it impossible to unmount that directory if it is a mount point). This script has overlapping functionality with the fuser program from the psmisc package, but has the advantage that it works on SMB mounts. Additionally, it provides a color, formatted listing of process IDs, executable names, current working directories, and the command lines used to run the programs. It works with varying-sized /proc/*/cwd fields.
The NIS UID Migration Scripts examine every file on a machine and checks to see if the UID should be changed, and if necessary, changes it based on a UID map. While orginally written for the consolidation of multiple NIS domains, it can be used for any type of large project that changes many UIDs. Examples include migrating to NIS or normallizing users UIDs on multiple machines.
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.