Simple Log File Monitor is a bash script that can be used to monitor log files or other text files and execute commands on the output of the logfile.
The motivation for this script originally was to be able to get a subset of a log file emailed to an email address easily while still being portable. Built to use as little as possible, a system with bash, wc, grep, tail, and date should be able to use this script, though a command-line email client would be required to send emails out.