Monitoring Server applications
This pages lists some links to products that may be useful for monitoring servers.
Tomcat
Lambdaprobe - http://www.lambdaprobe.org/d/index.htm
JMeter add-on sampler for rstatd - http://swirstatdsample.sourceforge.net/
visualization for results of swiRstatdSampler - http://swirstatdgraph.sourceforge.net/