It's very obvious that the chance of getting exactly 500,000 H+T is very small.

I wouldn't always run through the rain--sometimes I would walk, and of course I would still get soaked.

This got me to thinking: is their an optimum speed for traveling through rain which minimizes your wetness? For example, suppose you could travel at the speed of light. You would cut a swath out of the air and scoop up all of those raindrops in that very large area. The top of your head might not be wet but your entire frontside would be soaked! Of course we all know that if you go real slow through the rain you will also get soaked. So what's the best speed?

Theoretically--- It seems, intuitively, that a very fast theoretical speed(supersonic at the very least) would be ideal, because then the rain drops would be subjected to a large disintegrative effect. Complete disintegration is impossible(matter cannot be destroyed), but turning a drop into an infinitesimal mist would largely reduce the "wetness" factor.

Consider this - you have a fly and a 200 ton train travelling towards each other. Can the fly stop the train? Is the answer an easy no?

The pertinent question is what happens at the moment of impact. Now the fly can't suddenly change direction. It must slow down, come to rest and then accelerate in the opposite direction. At some point the fly's velocity must be zero - and since the fly is in contact with the train at that point, the velocity of the train must also be zero. Hence, as a result of the collision with the fly, the train will momentarily come to rest.

The train/fly simply have momentum vectors of very different magnitudes pointing in opposite directions.

But have you considered that every single particle comprising the train may come to rest at different times. The fly's impact will cause a (very small and almost imperceptible) vibration that will travel from the front of the train to back of the train. As this vibration travels through the train every particle will (for the briefest of moments) have a zero velocity.

If each particle(for the briefest of moments) has zero velocity, then implicit in your reasoning is that subsequently (but for the briefest of moments) each particle must then have infinite acceleration. If you don't realize this then I think you may misunderstand your own logic.

I don't think it's necessary to think of a the fly as a large system of molecules with independent velocities--for the purpose of the "paradox" it should suffice to think of the fly as a single particle.

As it turns out, at the beginning of this problem, a Canadian Dollar is worth exactly the same as the U.S. Dollar, and people are quite accustomed to using them interchangeably (including banks).

But, alas, the U.S. Government and the Canadian government get in a spat. So, the U.S. "devalues" the Canadian dollar 10%, so now they will treat it as worth 90 cents (U.S. currency). In retaliation, Canada does the same and "devalues" the U.S. dollar 10%, so they treat it as worth 90 cents (Canadian currency).

Enter <Wannabe>.

<Wannabe> goes to Alan's bar and purchases a 1 dollar Beer and pays with a 10 dollar bill (U.S.). He receives, in change, a 10 dollar bill (Canadian). He then walks across the border to Bob's bar and purchases another 1 dollar Beer, paying with a 10 dollar bill (Canadian), and he receives, in change, a 10 dollar bill (U.S.).

<Wannabe> proceeds to continue doing this until he finds himself spending more time in the restroom than Vladimir Kramnik.