Swatch can watch a log file and notify you by instant message when something occurs.
Watching Log Files
Services leave traces of what they are doing in log files.
Some services, such as databases and php, can be configured to record custom messages into their log files when something that applies just to your application occurs.
Watching log files is an excellent way of knowing what is happening with your servers in real time.
There are programs that will watch your logs and send you an instant message the moment that something occurs that interests you.
Fail2ban can watch log files, block an IP address, and send you an instant message.