Jon - good call re Las Positas. Man there are a lot of courses viewable from our major highways.. here's my try at a comprehensive list.
101, SF to San Jose and further:
Poplar Creek, San Mateo. Toughest hole on the course is right there by the freeway - long par 4 #2. You can see damn near the entire course.
Palo Alto Muni - tiny glimpses through the trees.
Sunnyvale Muni - again, glimpses through the trees. But when they're cut back you can see a lot of the freeway side of the course. And 237 goes right through it, so you can see the other side.
The aforemention RANCH AT SILVER CREEK (San Jose) - Hole #12, visible up on a mountainside, defying one's imagination as to where the rest of the course might be....
Coyote Creek (San Jose) - you can see pretty much the entirety of both courses. Pick a hole.
The Institute (Morgan Hill) - far off, up on a hillside, bunkers and greens visible in the distance.
Cordevalle (San Martin) - same thing, and you have to know where to look, but you can see the top of the driving range.
King City Muni - much of the course viewable.
That's as far south as we need to go.
I-280, SF to San Jose
Glimpses of SFGC through trees, same with Olympic Club and Lake Merced. Each course can be seen better from other roads on the other side, as has been mentioned.
Cal Club, as I said.
Crystal Springs (Burlingame) - much of the course viewable - very pretty.
Sharon Heights CC (Menlo Park) - some holes visible.
Los Altos CC - same
The I-380 spur runs right by Peninsula GC - much of the course visible.
I-680 offers Sunol, as Jon said... and Castlweood CC if you know where to look. Closer to San Jose, you can definitely see Summitpointe in Milpitas up on a hill. Farther north you pass right by Buchanan Fields in Concord.
I-580 gives you Las Positas in Livermore, as well as Dublin Ranch way off on a hillside in Dublin.
580 as it turns into I-5 runs right through Tracy G&CC.
The length of 880 from Oakland to San Jose offers no golf course viewing. I drove that for over a decade... sadly.....
I believe I've covered it all, at least close in to SF and SJ. And the best hole remains the one at Cal Club.