What's your favorite railcar?

Mine is SEPTA Silverliner IV in SEPTA's (Current) colors

Sleeper observation lounge, and when I'm eating, the dining car.

It hasn't been built yet

Kidding aside, Iarnrod Eireann's Rotem/Tokyu Class 22000 DMUs. There are others, but I'll just name that one.

Superliner sleeper car. Just wished the tracks, signals, and locomotives allowed slightly faster speeds.

Anything built by Budd pre-1970's. Bulletproof carbodies.

Personally, I love the Silverliner V. It's the most versatile EMU on the northeast corridor (and the only one that can run along its entire length), it has a railfan window, and I like the way it looks.

I am a fan of the Silverliner IIs. Groundbreaking, long-lived, utilitarian, pretty on the outside, and remarkably airy on the inside (though old-fashioned.) For that matter, I like MUs, LRVs, subway cars and streetcars in general.