agentsmith is a daemon that continuously monitors a log file for break-in attempts by remote hosts. Upon detection of a break-in attempt, it launches a user defined script or application, which can do virtually anything from sending mail messages to whatever else you might think of. The criteria for what is considered a break-in attempt can be configured by means of a regular expression.
tsf is a command line utility for creating timestamped copies of files. When invoked on a file, a copy of that file is created with a name made of the file name plus a timestamp. When invoked again on the same timestamp mark, a copy with a timestamp plus a sub-index is created, and so on. tsf provides an easy and quick way for creating timestamped copies of files before modifying them.