Hopefully will see J*J domestic fares up soon as I need to organise my internal summer (Japan) flights. I get the mails from them (in Japanese) and the most recent one said that fares are coming soon. Peach have some great fares out of Osaka at present but they only run until the end of June. Fuji Dream in/out of Matsumoto aren't too bad (advance fare 14,500 to Fukuoka) but schedule is limited. Air Asia seem to run their specials more regularly than J* so maybe get on their mailing list. Their J domestic arm starts in August.