Google Refine

Originally conceived and developed as "Freebase Gridworks" by Metaweb Technologies, Inc. and later after Metaweb Technologies was acquired by Google in July 2010, the software went through various releases and a re-branding beginning with Version 2.0 in late 2010. Google Refine is a power tool for working with messy data and allows exploration of data through analysis, visualization, conversion, and mining. It also can be used to reconcile data with data registries like Freebase, augment data from other sources, and perform transforms into different formats for other tools to consume. It allows processing sensitive data with privacy, since it is not a web service but a desktop app that runs on a computer.