Kinda like a video game.
This can be made many different ways and it's simple.
This will also save admins the trouble of trying to make a "Legend" to show off the achievements etc. In the end just a new meter and syncing either the same or putting them together would be nice.
One last thing. A page to show who has what achievements would be kinda cool to. So you see a friend with one more achievement then you so you think "well time to post" because you want to be on par at the very least with him.