My husband and I took turns driving. So the non-driving parent is the designated toddler entertainer. Two different styles:
With mom: Rotated playing with educational toys and looking through picture books, sang songs with Elmo, and the "buddies" performed a couple of dance numbers.
With dad: Threw blankets around, blew spit bubbles, played with food, and pretended they're Wolverine...then the toddler Wolverine and daddy Wolverine ate the "foot claws" afterwards. GIggles all around. Sounds more fun, doesn't it? 
Inside a sequoia tree.
Uh-oh, sand in the toesies.
Toesies drying in the sun.
She's going though a "Linus" stage right now...
Hmmm, are we on top of Moro Rock yet?
She also likes steering wheels at the moment.
And tries to climb over to the front of the car when parked. Vrooooom, beep-beep!