There are some rules, but if you meet these conditions you qualify for a free layover in Addis Ababa thanks to Ethiopian Airlines!
I had about a 20 hour layover while traveling from Bangkok to Milan. It would have been a bummer to have to spend that in the Addis Ababa airport! You do not need to fill out any applications or make special arrangements.
Just show up to the airport! They had paid hundreds of dollars and gotten transit visa for themselves and several children! They even paid for their own hotel and driver. I felt so bad for them! My passport was not stamped when I left the airport, but it was stamped when I entered the airport to catch my flight back to Europe. If you feel strongly about not having an Ethiopian stamp in your passport maybe you can speak to the folks at immigration.
So in addition to a free transit visa to Ethiopia for the duration of your layover, you will get a free hotel room, free transportation to and from your hotel, and free meals for the duration of your layover. You can arrange that in the Addis Ababa airport. I am definitely not a first class passenger so I got shipped off to Hotel Destiny with a handful of other people.
But note that the hotel assignments are pretty random. Hotel Destiny was sort of randomly located. The rooms were quite nice, especially since I had been a dirty backpacker all around Southern Africa for several months beforehand. Even though the inside of the rooms was actually quite nice, know that these hotels are pretty bare bones. The meals were simple but tasty. It was pretty neutral hotel food, so I set out to stuff my face with as much Ethiopian food as I could possibly find.
