Apache Tomcat is the most mature and stable servlet container out there used in a lot of production deployments. There are a lot of Tomcat resources out there and all Servlet / JSP books out there use Tomcat to showcase their examples.
The romantic image of an über-programmer is someone who fires up Emacs, types like a machine gun, and delivers a flawless final product from scratch. A more accurate image would be someone who stares quietly into space for a few minutes and then says “Hmm. I think I’ve seen something like this before.” - John D