This is a prototype simple single page web-app with no back-end allowing you to mix free-form text and calculations, along with the ability to use variables.

A more fully featured version is available at notepadcalculator.com.

Your calculations are stored within your brower's localStorage so that next time you open the calculator, it will contain your previous calculations.

OK, so this isn't the most original idea in the world. A year or two ago I heard about Soulver and at the time wasn't using OS-X so it wasn't available to me, and I made this instead. (I still haven't tried Soulver.)

I now use it within Fluid, which creates a separate OS-X application just for this calculator, making it convienient to open using Spotlight instead of the default system calculator. The downside of this is that it doesn't retain the localStorage between sessions.

I'm releasing this under the MIT licence, so feel free to do whatever you like with it! If you make anything cool, please let me know!