At times when there's no good calculator within the reach of your hand and you are in dying need to multiply two numbers or do some other simply math operation (2*2?), I suggest you use perl one-liner to do the job. Just include this line in your .tcshrc or .cshrc (or any other such file): 
alias calc perl -e \'print \"Simple Calculator\\n\\nResult: \" . \(\!\
+*\) .\"\\n\\n\"\;\'

[download]
(*note: you might have to prepend a full path to the 'perl' command.. something like '/usr/local/bin/perl' instead of simply 'perl')

To use it, just type 'calc (some mathematical expression)' in your shell prompt. 
Example:
    > calc 5*5
   
Will print this:
Simple Calculator

Result: 25
Of course, you could use 'calc' to compute any other valid math expression. ;-)

"There is no system but GNU, and Linux is one of its kernels." -- Confession of Faith

In reply to Simple command line calculator by vladb

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