Balogh and Solymosi's new paper doi.org/10.19086/da.4438
constructs $n$ points in the plane, no four in line, with max general-position subset size $O(n^{5/6+\epsilon})$, much better than the previous $o(n)$. I recently rescued a Wikipedia article on Solymosi, en.wikipedia.org/wiki/J%C3%B3z, adding book references for his results, but omitted my favorite (this one) because it wasn't published. Now it is, but the book reference would be too self-serving to add...

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