In the event-based multimedia I met Pil Ho Kim from University of Trento. He wears a camera that takes picture every minute from his life as long as other indicators such as temperature and creates his personal detailed log. This is part of his study on human behavior, He posted a presentation given at the ACM multimedia conference on Slideshare (it seems that he borrowed one slide from my presentation) entitled: "how to monitor human behavior". He is using ESPER for doing event processing, based on the multimedia events collected. This is a good example of using complementary technologies along with event processing.
A crash course claimed to take less than an hour entitled "A simple introduction to complex event processing" has been posted. This is done by example, which seems to be indeed very simple, finding "decreasing" or "increasing" pattern over two consecutive events and setting the color as green or red. The main emphasis is on the setting - how to obtain, define and use events, and configure the engine - threadpools, listeners etc... However not much about what event processing actually can do -- this is probably the next lesson.
Esper is contrasted with commercial products since its open source model allows developers to play with it, use it for toy examples, and for daily usage that is not necessarily a commercial application of big enterprise, in our days of enterprise computing this approach has certainly a role to play, it should be noted that Esper is not the only open source in this area, and that some of the commercial products allow free development version (not access to the source code, but enabling developers to use the product for these purposes for free).
Anyway -- if you wish to learn Esper, it is a good start.
