Carotenosis.
en.wikipedia.org/wiki/Carotenosis
So, like most people in this thread, I have woken up or during the course of the day, went from having no stains, to having fingertips and splotches of my palms colored orange.
It has only happened in the last 2 months, and I just got a confirmation from my Diabetic nurse on what was going on.
As I was recently diagnosed with Type 2 Diabetes, I underwent a complete overhaul on what I eat, in order to be more in line with managing the diabetes.
In the course of doing that, I have started eating more Egg, cheese and bell peppers.
With this change, plus the underlying conditions that I have, where I am likely to cause excess amount of carotenoids, which is the cause of the outermost skin layer getting tainted. For darker skinned people, the soles will likely also show the taint effect, as the Wikipedia entry states.
So there are two ways of getting this - over consumption of food that have high carotenoid content (list in wiki page), or underlying medical conditions that can cause an increase despite normal intake of the food.
In the end, Carotenosis is harmless, unless you are addicted to having perfect skin tone. 