Speedcrunch
is a small calculator application yet very powerful than normal
calculators you use and being availble for Mac , Linux and
Windows it can replace almost all default calculators availble.

Speed Crunch Desktop Calculator

Lets check out the features

• Its comparable to the scientific calculators you use. Not only it
  provides the scientific mode abut also displays like them. You can see all the expressions and scroll down or up.
• Auto correction in many places in case you had missed it
• Allows you save set of calculations you did. Meaning in case you need to quit in between you can save the list calculations you did and reload it again later.
• It provides you with set of Math Book, functions and variables.
• It even saves your session as History. In case you want to pull something back and use.
• Supports more then 20 languages.
• You can go full screen mode too.
• Supports Syntax Highlighting in case you forgot to close a bracket. You can set the colors.
• Auto complete mode. Just type the first alphabet of a function name and you will see them listed.

That’s long but no doubt makes it most powerful of all. Its
like you don’t need to buy a pro calci if you want to work all
time on computer.