I missed multiple calculators by default as in Windows. I found a simple Apple Script accessed with 'mcalc' that made this a bit easier for me.
do shell script "/Applications/Calculator.app/Contents/MacOS/Calculator -background >&/dev/null&"
I use multiple calculators for quick reference and when testing various implementations of my work, and was baffled that Apple explicitly stopped my from doing that with their stock calculator.app
open -n /System/Applications/Calculator.app
I missed multiple calculators by default as in Windows. I found a simple Apple Script accessed with 'mcalc' that made this a bit easier for me.
http://www.markc.me.uk/blog/files/MultiCalc.html