I can help you out!
First download tomcat from here: http://tomcat.apache.org/download-80.cgi . This is a server that will host dripstat for you.
Then unzip to some folder. Then download dripstat and unzip the folder into the Tomcat home directory.
Spring is another monster. Just get the JVM going first.
I better not see you ahead of me any time soon. :P
JVM is "Java Virtual Machine." People who run Java applications (traditionally servers like Tomcat and JBoss, although it's not limited to those) can install some code from Dripstat that reads how much memory that process is allowed to use on their server. 5% of that number is given as an automatic drip once every hour.
If you're not running a Java application that can be instrumented by the dripstat agent, there's really nothing for you in the JVM arena.
userscripts.org appears to be down, and the site is ill-maintained anyway, so for now there's an alternate way to access the script for installation: