(Feel free to disregard if this has been posted before. I looked but couldn't find a similar thread)

Xbox360acheivements.org has this feature.
They have a list of achievements for every game. That's not a suprise but what is cool is that there is an option button to "discuss" each particular achievement and tell others the way you got it.

Its a great concept but it may take a lot to implement. Thanks for hearing me out and keep up the good work.