When I closely look at the side of one of my fingers with one eye, I see:
From a closer distance, it somewhat looks like this:
The white-gray lines (in fact their color is also cream) are much narrower in reality (I can very hardly see the second one). I have doubt whether this is the result of a diffraction (my eye pupil playing the role of a small hole or slit) or the result of some sort of parallax caused by the diameter of the pupil (which is about 6mm).
Things get more complicated when I hold two of my fingers close to each other, then I see:
With a closer look, it's like:
In fact only the middle line can be seen properly if the fingers aren't close enough to my eye. Some say that this is the result of interference (the space between fingers playing the role of a narrow slit); but it seems like this has something to do with the lines of each finger (photo #1) like the lines of each finger somehow add up, like in the photo below for the diffracted light of two stars:
