Here is a list of known useful third-party tools and add-ons.
Filters
UrlRewrite
UrlRewriteFilter by Paul Tuckey (also hosted on googlecode) is a Filter that performs URL rewriting and redirections, and other typical tasks, like setting request attributes, headers or cookies.
It is similar to mod_rewrite module of Apache HTTPD server.
Security Filter
SecurityFilter is a Java Servlet Filter that mimics container managed security.
Realms
OrientDB Realm
- OrientDBRealm - Realms for Tomcat 6 and 7 that connect to an OrientDB
Web Applications
PSI Probe manager application
psi-probe is advanced manager and monitor web application for Apache Tomcat.
(It is a fork that continues development of the Lambda Probe application. The original Lambda Probe project is no more active since year 2006).