wcalc (command-line scientific calculator)

Wcalc is a very capable command-line calculator. It has standard
functions (sin, asinh, and sqrt for example, in either radians or
degrees), many pre-defined constants (pi, e, c, G, etc.), support
for using variables, "active" variables, a command history,
hex/octal/binary input and output, unit conversions, embedded
comments, and the ability to save history to a file and load it
from a file. Wcalc evaluates expressions using the standard order of
operations.

Wcalc uses intuitive expressions. For example, Wcalc will evaluate
5sin 4!-7*2(4%6)^2 to be -221.96631678.