I've thought of something like this a bit before as well, not a guillotine though. Make some kind of blade or something that will kill you on a time, take some sleeping pills, and get in position to fall asleep and never wake up. Can we make something like this a reality, without having something as complicated as creating a guillotine (assuming it would be very hard). This would be a good/reliable/painless (because you won't be conscious to feel pain) method in my opinion.