Another program addon i've done, this one is as professional as possible, with context help (thanks to yashied), and calculating as you type etc. Thanks to WBD for his improved _ToBase + _FromBase functions. My main problems was the calculating as you type, as it led to a very slow program at times, but after I figured out a good method to do the roman numerals, I was pretty much sorted! The other one was using contexthelp with a window set on top, and I still haven't worked that one out... T