I read an article recently, although I don't remember where, that talked about the Caffeine Power Nap.
I haven't done any research into this or read about it previously. However, I did sort of intuitively stumble upon the idea years ago.
You drink a strong cup of hot coffee and then lie down for a nap. You set an alarm or tell yourself to wake up in fifteen minutes.
When your internal or external alarm goes off, you have been able to rest (relaxed by the hot amber liquid) and in the meantime the caffeine has kicked in, so you feel alert and ready to tackle the rest of the day.
I admit to having used this technique at lunch. I have come home, feeling a bit fatigued by a morning of work, and made a cup of coffee. Then, I stretched out on the couch, let my shoes fall to the floor, and dozed off - or at least fell into deep relaxation. When I got up, the caffeine had kicked in and I slipped on my shoes and headed back to work.
Researchers looking into the Caffeine Power Nap recommend it for fatigued drivers. Stop at McDonald's and buy a large coffee. Pull to the edge of the parking lot and down as much of it as you can. Then, tilt your head back and relax. Awake refreshed and invigorated. Finish the rest of the cup as you drive on.