I long to see the sight of a Passat W8/W8 wagon (not actually sure if they made a wagon variant though)
Integra Type R... a legend among FWD sports cars. Someone in my area (I live in New York state) drive an R32 Skyline on a regular basis. I was shocked when I saw it.
There's a race track not far from home where a national road rally group comes to every year and I got to see cars like the Veyron, LaFerrari, various Lamborghinis, Porsches, McLarens, etc. It's a car lover's paradise, especially for supercar lovers. Hell, just today in downtown Detroit, I saw a 3-wheeled vehicle that looked like a Reliant Robin but couldn't get a glimpse of the brand that made it. One car I haven't yet seen in person though is an Alfa Romeo 8C. I'd love to see one in person!
Now that I think about it, I hope to see a newer NSX. Really sucks that I can't even spot one in Boston.