I think this is a great idea. I would go farther, and say you have 10XP to dole out amongst the node(s) that most helped. Give them all to one, or split it between, two, three... whatever. (of course doling out that XP would not be subject to the usual voting rules).
in reply to RFC: flagging solutions...
It would be a tremendous boost to an initiate, just noise to a saint.
This is a good idea because the node that most helped out the seeker of wisdom is not necessarily the node with the highest rep. Having a gold star along side the reply would be make the difference.
g r i n d e r