Optimizely - A/B testing you'll actually use.
UMLGraph - UMLGraph is a professional automated drawing tool that allows the designers the declarative specification and drawing of UML class and sequence diagram.
Evergage - Evergage's real time web personalization software can help you boost engagement, increase revenue and drive more conversions. Web personalization software that's easy to use.
yEd - yEd is a free desktop application to quickly create, import, edit, and automatically arrange diagrams. It runs on Windows, Mac OS X, and Unix/Linux.
Qubit - Qubit is a web personalization platform founded by former Google workers, using innovative technology to collect, store, process, and output data to optimize consumers' experiences on the web. Read more about Qubit.
Dia - Dia is a GTK+ based diagram creation program for GNU/Linux, MacOS X, Unix, and Windows, and is released under the GPL license.