Event Viewer - Get help, support, and tutorials for Windows products—Windows 10, Windows 8.1, Windows 7, and Windows 10 Mobile.
RealCalc Scientific Calculator - RealCalc Scientific Calculator
Numi App - Numi is a beautiful text calculator for Mac.
Qalculate! - Qalculate! is a multiplatform multi-purpose desktop calculator.
NumWorks - The graphing calculator that makes learning math easier.
GeoGebra Scientific Calculator - Free online scientific calculator from GeoGebra: perform calculations with fractions, statistics and exponential functions, logarithms, trigonometry and much more!