A few weeks after doing the first part of the ceiling fixes, I've finally added the lighting I was looking for. The room height is only 242cm, so my big rice paper lampions were cluttering up the ceiling badly and I wanted to replace them with some indirect lighting.
There are very small linkable fluorescent fixtures available, 22mm wide by 44mm high, 900mm long with a 21W tube, instant flicker-free start. Not very expensive, too: $39+tax a piece. I ordered three of them, for indirect light on top of my row of Billys.
A fifth Billy was bought last week, and for a whopping 5 minutes I thought I had some spare space for books...but no, cleaning up the stacked stuff from the other shelves filled the new cupboard immediately.
Moving the electrical outlet to where I need it was simple: find spot in wall without stud, cut hole in plasterboard, (bonus for solo workers: put a torch there to shine light into the hole), crawl into roof, measure spot, drill 2cm hole through wooden top plate, look for the light and use threading rod to send cable down. Took 30min with cleanup.
To get rid of the glare of the tubes (you can see them when you're standing across the room) I made blinds out of chipboard; that took a lot longer as my stupid perfectionism made me botch the iron-on edge veneer twice: Do Not Sand Down Corners Wearing Through The Melamine! Duh! Putting in the dowels in the right spots was a bit messy, too. But the result is very pleasing, apart from the fact that uplight makes every little imperfection in the ceiling finish stand out. The photos are not perfect: in reality there is no glare but my flash isn't powerful enough to light up everything.