The rewards for our posts do not come out of thin air. For that reason, we often feel like a post has been over-rewarded, since for every amount extra given to a post, it is money not available to all the other deserving posts out there.
Our current simple up and down votes are inadequate to express this view. When I initially see a post and it has $0.04, I may give it my upvote because I believe it deserves more than that. Later it may reach $1000, which may be far more than I believe it deserves, but my vote is still contributing to that value.
"Smart-votes" would allow us to express our intentions for the reward pool more clearly. What if I could choose a threshold or range to reward a post, as an alternative to a simple up or downvote? For example, my vote could say "I believe this is worth $100. My vote counts up to $100, but not beyond". Further functionality would include down-voting as well. "I believe this is worth somewhere between $100 and $1000. My upvote counts up to $100 and not beyond. My downvote counts if it goes beyond $1000". Ideally these downvotes would have no impact on reputation, since that is not the intent of the smart-vote.