After teasing this giveaway on its Facebook page for several weeks, OPI today announced the details of its amazing 100,000 Fans promotion.

If the company reaches 100,000 Facebook fans before Dec. 31, 2010, it will award 100 of those enthusiastic fans with six retired OPI shades — Kinky in Helsinki, Smokin in Havana, Hoodoo Voodoo, Parlez-Vous OPI, Sahara Sapphire, and Cheyenne Pepper. This may be a once-in-a-lifetime chance you to fill in some holes in your OPI collection.

How to enter to win:

1. “Like” the OPI fan page. (Already a fan? Then you’re ahead of the game.)

2. Fill out the entry form (found on the “100,000 Fans” tab on its Facebook page).

3. Increase your chances to win by encouraging your friends to enter to win as well. For each friend who identifies you as a referral, you receive an additional giveaway entry.

4. Once OPI tops 100,000 fans, the company will randomly select 100 winners!

Only U.S. residents who are 18 and up are eligible to win.

Good luck! Which shade of the six do you most want for your collection?

—Sree