You can also 'up vote' individual posts. Look in the right hand margin of the post and you'll see a number 0 with a ^ (up arrow) above it. If it's a particularly spot-on, helpful post, click the up arrow to acknowledge the user. The number will increment upwards by one. I think it may even change color. I'm not sure how the site tracks such things or if it goes into the user's profile.
Feinwerk