[pltrmzwy] How far have you travelled?

The total distance you have traveled, relative to the sun, is the arc length of a complicated cycloid (epicycloid) combining the motion of the Earth around the sun, the Earth-Moon system rotating around its center of mass, the Earth's rotation about its axis, and of course, your movement on the Earth.  All but the last are well-known values, I think.  The distance contribution of the Earth spinning on its axis depends on your latitude.

Another excuse to celebrate: when you pass particular distance milestones.