I have published out static content from Tridion to a Tomcat application server in a couple of implementations in the past. These have included a few integration points with 3rd party systems and were very straightforward to setup and configure.
It is worth noting that the latest version of Tridion also comes with a Content Delivery web service (also able to run in the Java application server), which (if you use Tridion's Dynamic Content Delivery) can allow external applications to access your content too. This can be very useful for mobile applications, etc.