A convoluted set of discussions on the newsgroup geometry.puzzles in October and December 2001 seems to be due to Conway (the various threads were a mess), with the conclusion that the lines which bisect the area of a triangle do not all cross the centroid but instead form an envelope making up a deltoid whose area is $\frac{3}{4} \log_e(2) - \frac{1}{2} \approx 0.01986$ times the area of the original triangle, and affine transformations show this a constant for all triangles

As an illustration:

This is not difficult to show, so counts as minor and lesser known. I once asked here if there was any direct relationship between the deltoid and $$\sum_{n=1}^{\infty}\frac{1}{(4n-1)(4n)(4n+1)} = \frac{3}{4} \log_e(2) - \frac{1}{2}$$ apart from giving the same value