For the month of February, you'll be able to get a download code for a level 100 Mew to use in Pokemon X, Y, Omega Ruby and Alpha Sapphire.
This year marks the 20th anniversary of Pokemon Red and Blue, and Nintendo is holding quite a few mythical Pokemon giveaways to celebrate. The first of these is none other than Mew, the legendary "151st" Pokemon that became a part of so many urban legends. For the month of February, head down to your local GameStop to pick up a free code for Mew (no purchase nescesary), which will unlock him in either of your Pokemon X, Y, Omega Ruby or Alpha Sapphire games.
Mew will be available only through February, and only while stocks last, so your best bet is to get down there sooner, rather than later. Pokemon TCG fans can also pick up the Mythical Pokemon Collection-Mew: which includes two special Pokemon TCG: Generations booster packs and a collectible Mew pin.
The good news for those of you in Canada or Australia/New Zealand who are sick of only the Americans getting the shinies, the promotion is also being held at EB Games stores across those your country.
Additionally, if you need even more Mew in your life, Nintendo has announced that alongside this promotion, Pokemon: The First Movie has been digitally remastered, and is now available for download on iTunes, Google Play, and Amazon store.