This is the web page for FindBugs, a program which uses static analysis to look for bugs in Java code. It is free software, distributed under the terms of the Lesser GNU Public License. The name FindBugs™ and the FindBugs logo are trademarked by The University of Maryland. FindBugs is sponsored by Fortify Software. As of December, 2007, FindBugs has been downloaded more than half a million times.
PyDev is a plugin that enables users to use Eclipse for Python and Jython development -- making Eclipse a first class Python IDE -- It comes with many goodies such as code completion, syntax highlighting, syntax analysis, refactor, debug and many others. If you want more details on the provided features, you can check here.
XPath Explorer (XPE) is a GUI application that lets you interactively experiment with XPath. Basically, you type in a URL (to an XML or HTML document) and an XPath expression, and it displays the elements or attributes from that document which match that