Thanks for everyone's advice.
I decided to totally disregard how our investments did yesterday and proceed with my plan to test drive new vehicles.
My check engine, ABS, and brake panel lights didn't light until the end of the day

I did check out the internet and saw that I am not the only person seeing these warning lights.
I think we have ruled out getting a new VW Passat. We just can't think of $30,000 worth of reasons to own a 2012 Passat vs. a 2001 Passat
I looked at the window stickers of the Audi's and kept walking
We were really impressed with the 2012 Ford Fusion Hybrid. However, I wish the new 2013 model was available because I really prefer the new body style for 2013. The dealer threw in enough discounts though to make it tempting
We were surprised with the how fun the 2012 Volvo S60 is to drive. We didn't expect that from a Volvo. However, this car was probably the least practical of the cars we drove today because of the relatively low mileage ratings and because the backseat is so tight vs. the other cars. My wife kept reminding me that a Mustang has even better acceleration than the Volvo
The 2012 Toyota Camry Hybrid is also a nice car, even if it a bit mainstream and common
It is interesting to see how some of the dealers try to get you to sign on the dotted line right away. I guess I am too cautious because I would just throw out a really lowball number when they would ask me what it would take for me to make a decision on the spot.
I will take a couple of days to think about it.
I hope we don't have too many more market days like we did yesterday or I may still be driving my 2001 Passat when I retire