For years, PC calculators have been trying to copy handheld calculators in both functionality and appearance. OpalCalc sets out to disregard previous conceptions, and instead we considered how a calculator should behave with a full keyboard in mind. The result is simplicity itself, but with almost spreadsheet-like capability. OpalCalc is ideal for everyone from students to teachers, programmers to scientists, or even for calculating your grocery shopping or holiday bill. Built in features include percentages, currency conversion, custom functions/variables, excellent documentation, colour coding, lightweight size, configurable GUI, hundreds of measures and functions, and lots more. The full version can be obtained with a donation of any amount (even a few pence). There is no time limit in the 'lite' version, just a 5 line limit which is very useful for most purposes.
OpalCalc features include: Lightweight footprint (less than 600k); Multiline support (notepad style); Configurable GUI with colour schemes; Built-in 'Quickstart' tutorial; Full colour coding; Multiple undo/redo, zoom in/out; Numerous built-in functions; Percentages & hundreds of measures; Currency support with conversion; Portable (260k from a pen drive); Custom variables and functions; Programmer syntax and functions; Custom number base support; Advanced notation support.