mod_top is a production monitoring tool for LAMP applications with user interfaces modeled after the popular Unix top. It plans to support PHP, Perl, Ruby, Python, mySQL, PostgreSQL, and Apache 1 and 2 on Linux. It can help you locate bottlenecks in applications, troubleshoot high memory consumption, understand CPU utilization under load, diagnose causes of slowness or heavy resource utilization, or discover database dependencies.
mpt-status is a query tool for accessing the running configuration and status of LSI SCSI HBAs. It is a heavily modified version of the original mpt-status-1.0 tool written by Matt Braithwaite. It allows you to monitor the health and status of your RAID setup. Currently supported and tested HBAs are the LSI 1030 SCSI RAID storage controller and LSI SAS1064 SCSI RAID storage controller. Since the tool uses the MPI (message passing interface), chances are high that the basic information regarding RAID status will be available for all LSI-based controllers.
Nagstamon is a Nagios status monitor with a UI that resides in the systray or as a floating statusbar on your desktop. It informs you in realtime about the status of your Nagios, Icinga, Opsview, Ninja, Check_MK/Multisite, Centreon, or Thruk-monitored network. It alerts you with sound and visual notification. Failed hosts and services are easy to connect with by SSH, RDP, and VNC. Custom actions can be run on certain events. It works best with GNOME, but also with KDE, Mac OS X, and Windows.
NCmatrix is a ncurses-based screensaver that produces the familiar display of vertical characters with added functionality to display network traffic. /proc/net/dev is polled to grab incoming and outgoing packet information, and the results are displayed as long or short colored streams of characters in the display, depending on the number of packets transferred since the previous poll. This code is based on the CMatrix codebase by Chris Allegretta.
net-status-monitor is a simple console script to test whether Internet connectivity is working. If it is, the script tells you the external IP address (in case your dynamic DNS provider is down). If not, it tries to find the point where the connectivity fails. The output is quite simple, so you can put it on your grandmother's PC. "Just tell me what the read line says" should give you enough information.
Passwd_exp notifies users via email of upcoming password or account expiration. Its simple modular architecture allows you to perform expiration checks on any data source you use (SQL databases, LDAP...), send expiration warnings only to desired users or group and on selected days only. Administrators can use it to review expired accounts in the system. Support for Linux and Solaris shadow (including LDAP and NIS systems) and BSD passwd systems is included.
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.