The name pretty much sums it up
A command line based, no buttons, RPN calculator
Note:
This extension will soon expire
The latest version of the calculator is available as a webpage:
https://celerisk.com/rpncalc/
Comes with all stack and math functions known (to me that is), features basic plotting capabilities and offers limited programming
1 2 3 * + <enter>
2 mode.precision drop PI Q <enter>