I was wondering what other people do to handle session timeouts in JSF applications. Right now my users either get kicked back to the login screen (less obnoxious) or sometimes get null pointer exceptions over managed beans (more obnoxious, but I think I've fixed this). Ideally I'd like them to go to a page where they are reminded that being idle for 30 minutes will disable their session and potentially cause them to lose data.
As a follow-up question, is there a way to see what managed beans are active in the application? It'd be neat if I could tell who was logged on (as they all get a managed user bean) by seeing which beans were instantiated.