I am pleased to announce the creation of my RPN calculator e^(j pi)+1=0 (ejpi for short).
https://garage.maemo.org/projects/ejpi/

The interface focuses on history manipulation and quick access to functionality through something like pie menus. It takes advantage of pythons type system under the hood for support of integer, float, and complex operations. For integers it tracks the base used and tries to persist that through the operations.

Another calculator? Well, I didn't notice SlideRule, Galculator, and Qalculate at the time I created this. In addition this provides more experimentation with touch screen interfaces.

RPN? Its a form of stack based operations. You put things on a stack (like a deck of cards), and then when you perform operations you pull values off of the stack.

Pie Menus? Yes, clicking on the buttons will get you the main function. Press and drag will let you access more (sometimes hidden) features. You can press and hold to see what the other features are. If you want to cancel, just drag into a direction that does not have any functions.

Quirks:

• "j" is used as the imaginary number rather than "i" (Its an electrical engineer thing)
• Calculations are done in floating point which can have a loss of percision, for example "e**(j * pi)+1" might not produce exactly 0

See
Homepage
Project Page
Package Page

Suggestions, criticisms, and code welcome.