Splunk is a tool to search, report, monitor and analyze real-time streaming and historical IT data. It collects logs from a variety of sources and makes them searchable in a unified interface.
For downloads and more information,
visit the Splunk homepage.
Splunk is basically Google Search for logs. Excellent for a single user or two doing analysis and forensics but I would not use it for real time monitoring. It is very resource intensive. It didn't scale well for me in the number of users that could simultaneously use a dashboard with a few queries on it.