For example, while it's true that an individual vote only has a small effect, consider the effect of say encouraging rationalists not to vote notice that this has an effect on more that one vote.

I always find it amusing how quickly people jump to knock off effects in these debates. If my actions and arguments have such effects surely those of other potential voters do as well. Doesn't this mean things add back to normality any my influence really is just the nano-slice it seems to be?