Keep-Alive 2 supports a wide range of monitoring options, including:

# Ping - returns roundtrip time.
# Web Server - including auth and SSL if required. Returns the page.
# Microsoft SQL Server - Connect to DB using SQL or Windows auth. Retuns connection state.
# MySQL
# SMTP Server - Returns server header. Supports SMTP Auth. Can send test mail.
# POP3 Server - Returns number and size of waiting messages
# FTP Server - Returns the home directory listing. Specify login or use anon. Option for PASV mode.
# Custom Port - Connects to a custom port number and returns response if any.
# Windows Services

You can be alerted to failures via email, SMS text message, or the Windows Event Log. Any command or application can also be triggered when a failure occurs.