Use Directory Monitor for real-time surveillance of directories and will notify you of file changes, deletions, modifications, and new files. You can optionally execute an application when a change occurs. Monitor users that have made changes.
NIC Watcher is a simple and useful Windows gadget that will monitor your Network Interface Controller (NIC, also known as a Network Interface Card) connection status.
A Firefox add-on that gives you some insight of the internal process of Adblock Plus
urlwatch is a pythonic URL watcher cronjob script.
A free Sierra Wireless developed Apple Mac client solution.
Free and open source Python application that watches your system log files, looking for hack attempts
Simple, cross platform, object-oriented, file watcher and notifier
nfswatch monitors all incoming network traffic on an NFS file server and divides it into several categories.