Exactly 17 years since Pokémon Crystal was originally released on Game Boy Color, Nintendo announced today that it's coming to the 3DS as a Virtual Console title.
This version has been slightly enhanced from the original. It includes Pokémon Bank compatibility, as with the other VC titles, but it will also include the ability to capture the mythical Pokémon Celebi (previously an event-only Pokémon).
Pokémon Crystal will be released January 26th 2018, and can be 'preloaded' on the eShop from January 8th. Here's the announcement trailer: