memtester is a user-space utility for testing the memory subsystem in a computer to determine if it is faulty. It does a good job of finding intermittent faults and non-deterministic faults. It has many tests to help catch borderline memory. memtester should compile and run on any 32- or 64-bit Unix or Unix-like system.
ProcMeter3 is a program for monitoring the system status and other information and displaying it in a series of graphs or as text. Most of the information comes from the /proc filesystem (cpu usage, load average , processes information, memory usage, network traffic, interrupts etc.). Other information is available for other sources (date, time, email status, log file length, disk status etc.). The program is modular and highly configurable.
The main purpose of LoFiMo is, as the name states, to monitor log files. It does this in real time, i.e. shows the contents of log files as they are changing. The user can connect to LoFiMo with a Web browser or use the console for plain text output. When using a Web browser, the output can be formatted with cascading stylesheets, which the user can define. Thus, it is possible to highlight certain log entries with different colors and fonts. It is also possible to play sounds or execute commands (send an email, play sound with a custom player, etc.) when a log entry matches a filter. LoFiMo can parse Apache style log files and syslog style log files. Among others, there are filters that can parse iptables logs and merge multiple log lines of Postfix into a single one.
INSERT (the Inside Security Rescue Toolkit) aims to be a multi-functional, multi-purpose disaster recovery and network analysis system. It boots from a credit card-sized CD-ROM and is basically a stripped-down version of Knoppix. It features good hardware detection, fluxbox, emelfm, links-hacked, ssh, tcpdump, nmap, chntpwd, and much more. It provides full read-write support for NTFS partitions (using ntfs-3g), and the ClamAV virus scanner (including a fairly recent signature database and a GUI). It provides partition handling with gParted and also has a network boot facility.
picocom is a minimal dumb-terminal emulation program. It is ideal for embedded systems since its memory footprint is minimal (less than 20K, when stripped). Apart from being a handy little tool, the source distribution includes a simple, easy to use, and thoroughly documented terminal-management library.