Sorry for the long absence, but I think I have more free time now. Inspired by the puzzles from Grandmaster Puzzles last week, I have created a puzzle that can be solved both as a Masyu and as a Yin Yang. As it turns out, this is a bit problematic to construct, as the density of clues required for the two puzzle types are different.
Thanks to Craig for pointing out that the first version of the puzzle is not unique. This has now been fixed.