Everyone that’s programmed anything in their life knows that things get boring. Most specifically, a programer knows that programming is an excellent way out of boredom. Hence, I present this.
calc# is my newest (most wasteful-time-gobbler) application written in Microsoft’s C#. It utalizes GTK# for it’s widget drawing, so it is fairly cross-platform. From the screeny, you can see it’s running in Linux quite well. I’ve also got it running under OS X. I haven’t tried it under windows yet, but provided you have you have GTK# installed and a decent CLI interpreter (Yes, the .Net framework *should* work, however, I use mono) it should run just fine. There are still a few bugs (the nifty keypad on the right of a lof of keypads isn’t working with it yet — I’ve only found out how to do that with Windows.Forms — I’m open to help 
) and other not so fun things. You can download the compiled version, or you can grab the souce.
As a hint to what might come, calc#’s younger [ugly] brother can be downloaded here. It uses Windows.Forms for it’s drawing (the prefrered method for .Net and will be for mono as soon as things start working) and I do know for a fact that it runs out of the Box in windows with the latest .Net framework.