LFT (Layer Four Traceroute) is a sort of "traceroute" that often works much faster than the commonly-used Van Jacobson method and goes through many configurations of packet-filter based firewalls. More importantly, LFT implements numerous other features, including TCP, UDP, or ICMP-based traces, AS number lookups through several reliable sources, loose source routing, netblock name lookups, and more. LFT also distinguishes between layer-4 protocols, which make its statistics slightly more realistic, and gives a savvy user the ability to trace protocol routes, not just layer-3 hops.
nefu (network fidelity utility) is a Unix daemon that monitors services over the network. It uses a "no false alarms" fault verification algorithm, and understands network dependancies. Natively-monitored protocols include ICMP echo (ping), SSH, IPP, DNS, HTTP, POP, NTP, IMAP, SMTP, and LDAP, as well as having facilities to execute external programs. Status pages are available via finger or the Web.
screen-scraper is a tool for extracting data from Web sites. It works much like a database that provides access to the information of the Web. It provides a graphical interface allowing you to designate URLs, data elements to be extracted, and scripting logic to traverse pages and work with scraped data. Once these items have been created, screen-scraper can be invoked from external languages such as .NET, Java, PHP, and Active Server Pages. It can be scheduled to scrape information at periodic intervals, and can automatically write extracted data to CSV files.
X Resource Graph (XRG) is a system monitor that shows graphs for CPU usage, memory usage, battery status, machine temperature, network usage, disk usage, current weather, and stock market data. It is designed to use as little overhead possible while showing a lot of information about the resource usage in a nice interface.
bmon is a portable bandwidth monitor and rate estimator. It supports various input methods for different architectures. Various output modes exist, including an interactive curses interface, lightweight HTML output, and simple ASCII output. Statistics may be distributed over a network using multicast or unicast and collected at some point to generate a summary of statistics for a set of nodes.
Dockside is a desktop companion application which provides quick access to a growing list of system and Internet information monitors through a familiar 'dock-like' user interface. The location, orientation, and overall look is configurable through an extensive set of user preferences and built into the theme engine.
JDiskReport enables you to understand how much space the files and directories consume on your disk drives, and it helps you find obsolete files and folders. The tool analyses your disk drives and collects several statistics which you can view as overview charts and details tables.