Allow voting on comments
Upvoting an answer is great, but often times there are comments further down in the thread that should be acknowledged. I'd like to see a way to vote on comments in threads with something either similar to the upvoting system for answers or by just being able to give them a star or something similar.

I like the idea of a “this helped me” counter for comments. Voting doesn’t work so good here because votes change the display order so the highest voted are on top and comments need to remain a linear fix-ordered list.
The concern here is that there are several ways to vote, rank and rate things already and adding another could increase the complexity of the site overall. That said, doing something here is a good idea so we will do more research to determine what would work best.