PIKT is a cross-categorical toolkit for monitoring and configuring systems, organizing system security, formatting documents, assisting command-line work, and performing other common systems administration tasks.
ntop is a Unix tool that shows the network usage, similar to what the popular top Unix command does. ntop is based on libpcap and it has been written in a portable way in order to virtually run on every Unix platform and on Win32 as well.
"SAINT is the Security Administrator's Integrated Network Tool. In its simplest mode, it gathers as much information about remote hosts and networks as possible by examining such network services as finger, NFS, NIS, ftp and tftp, rexd, statd, and ot