I bought myself a "nice" car when I was 23...a 2002 Yukon Denali. I say "nice" as I'm sure some of you wouldn't consider it nice. It was enjoyable...especially when I was single. Became a little impractical when I ended up having a long commute and I turned it in for a used car until my commute shortened. Once my commute came back to reality...I went and got a Toyota Tacoma. My priorities had changed slightly and having a truck was desireable for my hobbies/lifestyle.
Now that I've settled down, bought a house, etc...I don't see me getting rid of my Tacoma until the engine dies...and I can't revive it. That being said...I'll be buying my wife a "nice" car in a few years. Her 04 Civic will technically last forever...but I'd like to get her into something a little bigger/safer and with 4 doors for future family plans (she has a Civic Coupe). Current ideas:
Audi A3 or A4
Lexus IS250/350
BMW 3 series
Infiniti G35
Pontiac G8
Honestly, of those cars, I really want the G8 or the A3...but we'll see how the G8 really pans out and what her preferences end up being. An A3 with the 2.0T and DSG transmission is also really tempting for all around utility, fuel economy, and fun. A good car to take on trips (I love nothing more than a fun road-trip...half of my college experience was taking mindless road trips with no specific plans).