Another entry in the “Why didn’t I think of that first?” category of Facebook apps, Pieces of Flair allows you to add customizable buttons called “flair” to your Facebook collection.

When it’s working (the profile page integration isn’t quite always working for me), Pieces of Flair provides another fun way to personalize your profile and send things to friends. While not quite a “game” per se, collecting items is an addictive hobby for many.

With Pieces of Flair, you can buy from a countless selection of button designs (many are user created) or make your own. The game’s economy (which lets you purchase and send pieces of flair) functions by users sending their favorite content to someone else, inviting friends to the application, or logging on once a day.

These are basic steps and good ways of retaining users. With over 400,000 daily active users, Pieces of Flair is growing quickly, and just got acquired by major Facebook application developer RockYou.

I only wish they’d think of a clever way to sell people these buttons in physical form. I’d buy a few of the buttons that say “Save Ferris!”

Gameplay: 6?

Developers: 7

Percent Complete: 60