Overachiever:
Overachiever is another addon aimed at modifying the achievements interface and aiding you with completing your achievements. It has many features, such as the ability to move the achievements window, a search tab, suggestions of achievements to complete, enhanced achievement tracking, and added information to tooltips if related to an achievement. Features seem to be added with every update, as the addon is still in development, and the addon covers most every aspect of achievements.
To read all that it can do, see its
download page.
If you are interested in other addons aimed at achievements, you can check out
Urban Achiever (a previous PotW), or you can simply
search addon descriptions for the word "achievement".
For previous Picks of the Week, see
here.
Are you the author of a mod that you think belongs in this spotlight? Just upload/update it to WoWInterface, and it will automatically be considered for that week's Pick.