Square Enix announced one of the new features in Dragon Quest VI: Realms of Reverie. The remake has a passive wi-fi mode like Dragon Quest IX and The World Ends With You.
Before you turn on passive wi-fi you need to create a dream character. Dragon Quest VI lets players choose kings, queens, monsters, and a few familiar faces from Dragon Quest V: Hand of the Heavenly Bride. After picking an avatar you set a location, background, write a message, and select a style of speech like sexy woman, cute girl or serious man.
All of that data is used to make a custom dream, which can be transmitted to other Dragon Quest VI players while your DS is clamshelled. If another player passes by with Dragon Quest VI on they automatically download the dream and can watch it on their DS. Think of the whole system like random dream encounters in real life.
Dragon Quest VI: Realms of Reverie is scheduled for release on January 28, 2010 in Japan.