I was thinking about this thread yesterday while I was in the driveway with my 2-1/2 yo daughter. We bought a bike trailer for her yesterday. I hooked it up to my wife's bicycle and left it in the driveway. I could see her face light up and point at it from her car seat when they arrived home from work/daycare. I got her out of her car seat and she started pointing and looking and telling me she wanted to get in the Tunnel - every plaything she has that is tent based is a tunnel, we need to work on her vocabulary. We put her in the trailer and rode her around for a while. She bawled her eyes out when we took her in for dinner.
We have a picture of her in a friends Elise from the Deven's tour last summer. I sit her in the Trans Am and she loves it. We're taking her to a local cruise night tonight. She loved it last year. Her favorites were a Harley and a 1st gen 454 Camaro. We'll see what she goes for tonight.
What I was reminded of yesterday is her dad is putting money away for a kart already.

She can compete in Solo event in 6 years. I hope my daughter will be interested enough to drive with me.
The kart program is pretty active in New England. (hope they don't mind me using them as an example)--> We have a three generation family running - Bill, Mark, and now Kayla Goodale. Mark's wife/Kayla's mom also drives. Mark is our current Solo Chair. Another family runs karts in solo - dad, mom, son, daughter. Dad and son also run with karting organizations on road courses and hit some pretty high speeds.
Four or five of us in NE have girls about a year and a half apart. Looks like we'll have a big class in '12.
We've had and have several parent-children cars, too.
Some of our core workers began "racing" as youngsters with their parents. Not only are the young folks learning car control, but they are also learning about competetion, winning and losing, responsibility, gaining friendships, and participating in an event as a family. Can't say that about alot of families these days.
I'm looking forward to driving with my daughter if she wants to . It may give me some comfort when she asks for the keys to my car someday. We'll be doing something together - although I may need to take up ballroom dancing at this rate to do things with her. I'll have less fear of her getting injured than if she were involved in, for instance, soccer or gymnastics (yes, I've seen some scary injuries in soccer games)
I realize you're older than the kart kids, but it may help with dad from a dad's perspective.