[DrHankPym]

It's also easier to remember that the area of a unit circle is pi.

Also, e ^ (-i * pi) + 1 = 0

[RuggeroAltair]

What's the kinetic energy of a unit speed, unit mass?

What's the potential energy of a unit distance unit spring constant?

What's the energy of a unit mole, unit temperature in Boltzmann units?

:-)