Tokyo-based interactive content provider Dwango announced today [JP, PDF] the start of a download service of a very special kind. Now Japanese cell phone owners are able to get ringtones that are only audible to dogs.

The service is dubbed Inu ni shika kikoenai chakushinon (ringtones only dogs can hear). Dwango says their idea is absolutely groundbreaking. Downloads are free for subscribers of the dwango.jp tori houdai (download flatrate) service, which is only available on DoCoMo’s proprietary mobile web system imode.

Truly a bizarre idea, even by Japanese standards. By the way, Dwango is listed on the first section of the Tokyo Stock Exchange.