The last log ended with a view down to my "extended basement". After walking down a long staircase, you come to a large room:
It's not that pretty, but it works.. as a room. Left-to-right: Skeleton xp farm, redstone/mechanical/sorting room, store room, staircase to the little building outside the front of the house, a few holes, the mine, enchanting room (behind the sword).

The skeleton-dungeon-farm-xp-grinder is the most interesting thing down here, so lets have a look at that:
On the left is the viewing hatch, then in the centre is the control panel and fully-unfunctional binary mob counter. I figured the counter could only count to 63, and to get to a decent level you needed more than 63 skeletons, so I never really started the workings behind it. Using the levers and button on the control panel allows you to open the hatch, and toggle the water and lights on and off, as shown in this gif: That system is really useful for doing additional work or testing in and around the spawning room. You can just about see the elevation chamber at the back there, which scoops up the skeletons, sends them high up, over the top, then they fall down over....
Here! Left lever: Auto-burninate (kills any skeleton unlucky enough to be in the tiny tube - uses lava). Right lever: Item collection. Yep, that's what the dark line below the skeletons is; a hopper! You sit in the room and wait for skeletons (If I want to get to level 30 I'll AFK for an hour or so), lean in, punch the ske...