Python library and shell utilities to monitor filesystem events
Eye candy ARP spoofer for Windows
Count the number of people around you by monitoring wifi signals
PotHead
Bandwidth Monitoring Tool; Console SNMP traffic monitor
Monitoring your infrastructure for free.
nagios-statd patch for use with python >= 2.6
A flexible, extendable content filter
DeepDive Sentinel is a Windows BETA tool for diagnosing connection