LZO is a portable lossless data compression library written in ANSI C. It offers pretty fast compression and very fast decompression. Decompression requires no memory. In addition there are slower compression levels achieving a quite competitive compression ratio while still decompressing at this very high speed.
mkCDrec (Make CD-ROM Recovery) makes a bootable (El Torito) disaster recovery image, including backups of the Linux system to one or more CD-ROM(s) (multi-volume sets). Otherwise, the backups can be stored on another disk, NFS/CIFS disk, or (remote) tape. After a disk crash or system intrusion, the system can be booted from the CD-ROM and one can restore the complete system as it was. It also features disk cloning, which allows one to restore a disk to another disk (the destination disk does not have to be of the same size, as it calculates the partition layout itself). Currently, ext2, ext3, minix, MS-DOS, FAT, VFAT, Reiserfs, XFS, and JFS filesystems are supported. It can restore disks in Software RAID and LVM mode. It supports the One Button Disaster Recovery (OBDR) mode, which simulates a bootable CD-ROM on tape.
makeself is a small shell script that generates a self-extractable compressed TAR archive from a directory. The resulting file appears as a shell script, and can be launched as is. The archive will then uncompress itself to a temporary directory and an arbitrary command will be executed (for example, an installation script). This is pretty similar to archives generated with WinZip Self-Extractor in the Windows world.
MAT is an easy-to-use network-enabled UNIX configuration and monitoring tool. It provides an integrated tool for many common system administration tasks, including backups, replication, and running commands on hundreds of machines at once. It includes a warning system for potential system problems, and graphing of many common system parameters. MAT provides many of the tools a system administrator needs during the day, including DNS, NIS, Backups, and Replication. One can run a MAT command on many hosts at once. A simple editor window is provided which can modify a set of machine's configurations in one session.
mcrypt is a program for encrypting files or streams. It is intended to be a replacement for the old UNIX crypt. It uses well-known and well-tested algorithms like BLOWFISH, AES, ARCFOUR, CAST-128, and more in several modes of operation. It also has a compatibility mode with the old UNIX crypt program and the des program found in Solaris.