I haven't been paying so much attention to the carnival of mathematics lately, so I've skipped some issues — it seems we're already up to Number 47 (the Star Trek edition).

Two of the entries caught my attention. First, the incenter is the Nagel point of the medial triangle. This was known (and there are many similar ways of deriving one triangle center as a different center of a related triangle) but The Advanced High School Math Project supplies a proof.

And second, Quomodocumque gets into some deep water attempting to count the order-types of planar point sets.