I've recently become somewhat of an expert on train-riding. There's an active Amtrack line between my town and my parents', so if I am traveling alone, I often take the train. It's become so frequent that I have a preferred spot to in, I know the conductor by sight (looks an awful lot like my brother-in-law) and can tell whether or not we will be on time.
For all the wise cracks about flying and plane delays, the train is worse for getting to places on time. On one trip, we stopped for five minutes or more at every station and, let me tell you, the train stops at every Podunk station between our houses. If there is a freight train, my train had to stop to let it pass. At one point, we were going backwards! It drove me nuts!
Because of this, it takes longer to travel by train than it does to drive and certainly to fly ("hurry up and wait" time at the airport included). I can get to my parents house (door to door) in 4.5 hours. Station to station, it once took six. (Did I mention the whole going BACKWARDS thing?)
Food pickings can be slim too. They offer a variety of beverages and microwave meals but the days of a hot, cooked meal on the train are long, long gone. After six hours on the train and nothing to eat but a coffee and chocolate pastry at home, I never made that mistake again and always carried food with me. (Let's not talk about the vegan "bar" I bought at my train station.... we were daring each other to eat it! I still say it should be part of a hazing experiment at frat house.)
But you want cheap? Train travel is super cheap. I can't get to my parents' town for less than half a tank of gas in the mini-van but I can travel by rail for $30. It's also great for people watching. I've had some lovely conversations with people and had a moment where I was sure we were all going to be part of an episode of "I Didn't Know I was Pregnant!" live and in person! (We weren't. But for a moment there...) I've also listened to really bad country ballads ("This is the story of the War of Northern Aggression. . . .") and seen an entire Amish family get on. All of those are experiences I wouldn't have had in my car.
Another bonus? I don't have to pay attention. I get on, plug in my phone or laptop and zone out for 4-6 hours. I don't have to worry about safety instructions, pay attention to the road or listen to children squabble. (I travel alone when I take the train.) I read, I nap, I day dream. Whatever. It's kinda nice!
As I told my parents, train travel is great if the journey is part of your trip, if you need a cheap way to travel and don't have to be at a certain place at a certain time. It's also great if you want to be in your own zone for an entire trip but don't have a second driver. Otherwise... stick to the planes or cars.