Jiffy Script, Inc.
rkd
"Rootkit" detector, written in Perl.
fwlogs
Firewall log parser.
service_freq.pl
This reads nmap XML output files (generated with nmap -oX or nmap -oA)to generate a list of services and how frequently they appear on the scanned network (or, at least, XML output). This was written in conjunction with Vulnerability Testing Against a Predominately UNIX-based Network.