In my business, I often do data converion. Google Refine aids in that considerably. For example, you’ve merged several mailing lists and discovered that data in one of the fields has been entered multiple ways and needs to be standardized. Google Refine allows you to do that with a couple of mouse clicks. Sweet.
Google Refine is a power tool for working with messy data sets, including cleaning up inconsistencies, transforming them from one format into another, and extending them with new data from external web services or other databases. Version 2.0 introduces a new extensions architecture, a reconciliation framework for linking records to other databases (like Freebase), and a ton of new transformation commands and expressions.
It works on CSV text files, as well as Excel, Google Spreadsheets, XML, and JSON, and certainly looks like it can save hours of tedious work.