My mule impression

This week I run into Mule. This is an open source ESB (Enterprise Service Bus) and is all about integration. In one article it is described as a kind of Leatherman of integration tools.

Here the best examples I have found so far:

• A File Sucker-Example, monitoring a directory for files to import. This is based one Spring and Mule.
• A Snowdude-Example why an ESB is useful

Another ESB open source implementation is part of the JBoss tool collection. Is a comparison out there?