Now here is a campaign of which I approve: the outdated and
outmoded pi deserves to be replaced by the intrinsically more
useful tau (= 2 * pi). Why is that you ask, because pi is the
ratio of the circumference to the diameter of a circle and the
area is pi*(radius)^2, which is pretty straightforward. Maybe,
but the area formula (tau/2)*(radius)^2 shows us that the area
of a circle is the sum of a series of infinitessimally sectors
(ie. very thin triangles). The tau form of the formula is much
more like all those other quadratic formulae for energy
(1/2*m*v^2), distance (1/2*a*t^2), etc etc, because what is
really going wrong is that pi is only half the value it needs to
be. The circuumference of a circle is pi*diameter but that is
2*pi*radius, or tau*radius. As Leonnard Euler would have told us
exp(i*tau)=1, which is just too cool for words.