This is a set of command line utilities for manipulating large tabular data files. Files of numeric and text data commonly found in machine learning, data mining, and similar environments. Filtering, sampling, statistical calculations and other operations are supported. The tools were originally developed in Perl and used for day-to-day work in a large scale data mining environment. One of the tools was re-written in D as an exercise exploring the language. Significant performance gains and agreeable programmer characteristics soon led to writing additional utilities in D. Information on the D programming language is available at dlang.org.