Peter van Heusden:
> Why in the world is this - a form of co-ordinated tactical voting - not
> legal?
>
> Peter
> P.S. I think this will have about as much effect as 'click here to end
> world hunger', btw.
The material effect of one vote is infinitesimally small and cannot be said to affect the outcome of events.
Therefore, if "trading" one's vote is entertaining or meaningful to the voter, she or he should by all means go right ahead and do it -- it's harmless as long as one doesn't feel bad about doing it.