What is the best way to host potentially dozens of fairly trivial Java web applications on a single machine? These will be for different clients, and so having them isolated from each other is important, so that if one goes down, they don't all go down. I realize Tomcat can handle multiple apps on its own, but having them all run in a single tomcat instance sounds a little scary to me. An instance of tomcat per app also seems silly, since these apps are likely to be fairly basic.

Any thoughts?