Pocket calculators are both the ultimate evil and the absolute good these days. True, they've relieved mankind of trivia calculations, yet when first graders tend to use them for the most basic arithmetic operations, this can't be considered very encouraging. The Windows operating systems family has its own clone of pocket calculators, which you undoubtedly used at least once. What we're going to look at today is a similar calculator that operates in another digits' system - CalcRoman.
     CalcRoman is a calculator tool with all the basic functions of the default Windows one. However, this one operates with Roman numbers, not Arabic ones. This makes all the difference. If you study ancient Roman culture or just figuring out what means XXIX, you're on the right trail. This tool lets you do the basic arithmetic operations with the Roman numbers as well as convert them to Arabic ones and back.
     The few things that put one off this curious utility is that all comments and error messages are in Portuguese, not English, and the fact that as you try to type a Roman number without the prior knowledge how to do it all sorts of warning messages, again in Portuguese, pop up. All in all, the program is funny to learn and play around with.