the Spanninga Pixeo is an excellent, inexpensive solution to the problem
of how to keep your seatpost
and/or packrack clear of taillight attachments.
being Dutch they do not flash, which is, sensibly, against the law in several European countries due to the distraction
and just general fucking annoyance
of sitting behind a flashing LED in traffic.
runs on two AAA batteries, which means you can use rechargeables.
three thumbs up.
which makes it a bloody mystery why no-one in Aus stocks them.
I got them from here.