J-Pillow Travel Pillow
I know it looks like a big ol' dumb...J...but the J-Pillow is the undisputed champion of all the travel pillows I've ever tried*. Its bubble letter "legs" create a golden ratio of ergonomic support for my head and neck. I can lean back and tilt to the right or left without the weight of the former dragging down the latter and cricking it up at a 45-degree angle while I sleep. The chin rest also prevents Bobbing Head Syndrome so you don't jolt yourself awake just as the dream about the chick on your girlfriend's girl magazine is getting good.
If endorsements from more reputable sources than I am are important to you, the J-Pillow also won the British Invention of the Year award in 2013. And multiple thousand reviewers give it an average of 4-1/2 stars.
*Disclaimer: I haven't tested every travel pillow on the free market, but I have gone through and discounted my own bed pillow (too big), airline-supplied pillows (vomit), inflatable neck pillows (deflate during use), and this Total Pillow donut (too hard and too bulbous).