BC is actually super useful when in the shell (less fuss than firing up python shell or similar). I use(d) it a lot, though didn't dig deep into what it can do, beyond setting `scale=2` (set output to two decimal places) when dealing with currencies etc.

If I'm elsewhere in GUI tho, Meta+C (shortcut I have for the calculator app) is faster than firing off terminal, starting bc, then closing it up after oneline calculation.

.. at least, it should be faster ;-)