Hi!
I just came back from Japan, and realised that there are quite a few good TP runs available that might be of use to some of us.
The best I could find was Okinawa (OKA) - Miyako (MMY), which when booked in advance in "J Class" (JAL domestic premium* cabin) is £60 rtn (JPY 11,200) and yields 80 TPs, working out at £0.75 per TP.
OKA-MMY isn't terribly useful for people not headed to the far south, so the cheapest I could find from Tokyo was HND-KMQ (Komatsu) which works out at around £116 rtn for 80 TPs, so £1.45 per TP.
Hopefully this'll be handy for someone needing an extra few points.
*"J Class" is a slightly larger seat than economy, but with roughly zero other benefits other than the extra Tier Points. No lounge/priority boarding/enchanced catering). Most (but not all) 737 size planes and up have a J cabin, and the upgrade fare (subject to availabilty) is JPY 1000 (~£6). As far as I can tell, all economy tickets can be upgraded at the check in desk. I don't know if miles bookings that are upgraded will earn TPs.