KDDI au today announced a trial campaign for free international SMS messages (short messages sent directly to a phone # rather than an address).
The free trial period is from 11/15/2012 - 1/15/2013. SMS messages are normally 100 yen to send (free to receive).
Here's the catch - this campaign is only for users applying to use international SMS for the first time, AND - you only get to send THREE messages for free (within the trial period). You will be billed for these three SMS, but they will be subtracted from your Feb. 2013 bill.
Details of the campaign (J): http://www.001.kddi.com/cpsms/
SMS JPN info page: http://www.001.kddi.com/sms/
SMS ENG info page: http://www.001.kddi.com/en/sms/index.html