Don't found a possible name yet, but I think a badge for downvoting would be a great idea.
WAIT! Don't click downvote already, it's not about "normal" downvoting, it's ment to receive after you've done a moderation-downvote.
Someone asked a question, and someone answered this with a worse solution or not an solution at all. Then, we downvote to let them know it's not the right answer for this question. This is a great feature of Stackoverflow, but I see many answers with wrong content which are not downvoted at all.
To stimulate downvoting answers that really needed a downvote here's my Bade idea:
You're the first to downvote and the answer/question reaches a score of -10 after that for at least X (25 or maybe 50?) times you'll be rewarded with the "Helpful downvote" badge.
I'm still looking for a good name, but I think this will be a great addition to the badges as I find it really helpful to downvote wrong answers given in a question. Starters of a language should be pointed to the right answer and the downvotes are an easy tell for them to try out another answer given in the thread.
I just found this thread: New Badge Idea: Willing to Sacrifice
It's a great name "Willing to sacrifice", and combining that idea with mine would create a great badge.
- First to downvote a question which will reach a score of -10 at least X (25, 50 or maybe even 100) times and left a comment
What do you think?