I've seen this similar feature in various forums, and personally I pretty much like it.
If you're not very familiar with it, it's a some kind of a "like" for a post. If you somewhat like or support the post's content, you can just simply hit that "+1" button in the corner, or where ever it is. Your +1 will be displayed underneath that +1'd post.
Just a little nice addition that won't do bad things to the forum itself, I believe. I don't know if it's possible to implement into this forum code style thing, though.
Any +1's for this idea?