Rapid Software Testing by http://satisfice.com was a interesting training I attended to. One of the introduced methods is spot check, or I would call it log analysis. Logs should be used to analyze or check a product. Log files can harbor interesting data 
XSD Diagram is an open source viewer. It depends on the Microsoft .net framework 2.0. The Linux port it runs under Mono. It has a similar capability like Altova’s XML Spy to navigate and display XML tree structures.
https://www.random.org/ generates random numbers, that you can use for testing.
JMH is a Java harness for building, running, and analysing nano/micro/milli/macro benchmarks written in Java and other languages targeting the JVM.
http://openjdk.java.net/projects/code-tools/jmh/
Atlas is a wiki-like, git-managed authoring platform for creating books. http://chimera.labs.oreilly.com/books/1230000000065/ch01.html
zpub is a authoring and publishing system for docbook documents. The SCM behind is Subversion. From my understanding it automatically generates the desired output after each commit and notifies interested/involved persons.
apt-get remove allows to uninstall software packages for Debian and Ubuntu. Some software may still have configuration stored on your system. If you don’t have used apt-get purge, the config files still resides on your Debian installation. This post illustrates how to remove these packages.
In JPA it is possible to create directly a new object from JPQL SELECT statement, instead of fetching the result list and mapping the attributes. The JPA supports the constructor expressions for that.
This post demonstrates a part of inheritance with JPA 2. Abstract entities (classes) can be used to query their concrete subclasses.