IPTraf

"IPTraf is a console-based network statistics utility for Linux. It gathers a variety of figures such as TCP connection packet and byte counts, interface statistics and activity indicators, TCP/UDP traffic breakdowns, and LAN station packet and byte counts."

(http://iptraf.seul.org/about.html)

Libnet

Libnet is a generic networking API that provides access to several networking protocols.

See http://www.freebsd.org/cgi/url.cgi?ports/devel/pcre/pkg-descr for a more detailed description.

Libpcap

"Libpcap is a system-independent interface for user-level packet capture."

(http://www.freebsd.org/cgi/url.cgi?ports/net/libpcap/pkg-descr)

Libpcre

"The PCRE library is a set of functions that implement regular expression pattern matching using the same syntax and semantics as Perl 5, with just a few differences."

(http://www.freebsd.org/cgi/url.cgi?ports/devel/pcre/pkg-descr)

Lynx

A non-graphical, text-based internet browser.