Japanese publishers seem to be trying to one-up each other in donations. NC Japan has one of the most generous offers of all: a full months earnings!
The Lineage publisher said today that it will donate 500 million yen to earthquake relief efforts. This corresponds to one month's earnings, it said.
It will also be using reduced power for game servers (although not shutting down like some other games) and providing payment support for quake victims who can't log in for extended periods.