If you were debating whether you'd see Star Wars: The Force Awakens in 3D or not opening weekend, this news might sway you. Heck, it might even make you go see it four times in a row (like you weren't going to anyway?).
RealD tweeted out the limited edition 3D glasses that will be given away, presumably at opening night/weekend showings until supplies last. In past years, they've teamed with Disney on Marvel Studios films, offering 3D glasses styled off of Captain America, Iron Man, and more. For fans who have passive-3D TVs at home, these collectibles can be reused there as well as at any (standard-sized) theater.
The collectibles this year, for those who hate reading smallish type on an image, are modeled after Captain Phasma, BB-8, a First Order Stormtrooper, and Kylo Ren. That means 3/4s of the options are Dark Side oriented, if you're keeping track. BB-8's has his little eye camera, Phasma has the metal sheen - yeah, you'll want these.
It should be noted, these types of 3D glasses typically work only with standard theaters - IMAX 3D is a different size and style of glasses, and they don't work across sizes. Make your plans (and ticket purchases) wisely.
We've reached out to RealD for more information on availability, and will update accordingly.