According to this site:
http://www.toyota.com/vehicles/hov.html
you can only drive in the HOV lanes in New Jersey, Florida and Virginia. Florida requires a $5.00 window sticker. I wonder if they are reciprocal? There are times I would have liked to use the HOV lanes heading north through the DC area.

Yes, that's correct, for example NY requires minimum 45MPG to be considered for HOV lanes permit with single driver, I wish they had some federal standards for this, since it's getting confusing especially for people living on the borders of 2 states with each state having it's own rules.

My understanding in VA is that you can drive a TCH on I-66 inside the Beltway, but to use the HOV lanes on 95 between Triangle and the Beltway, and I-395, you had to have registered the vehicle before a specific date, which has passed: http://www.virginiadot.org/travel/re...s/HOVFINAL.pdf

I called the VA State Police and spoke to trooper who said he know of no reason why I couldn't use their HOV lanes. He said that I might be stopped but as long as I met Florida's rules and regulations there shouldn't be a problem.
I will definitely give it a try. I will write down the Barracks and their number and the date I called and explain what I was told there shouldn't be a problem. Maybe......I hope. LOL

Just yesterday I was in the HOV lane on I-66 in Northern Virginia, and there was a Camry Hybrid right behind me in the HOV lane, with just the driver and without the required license tag.

Once we both passed inside the Beltway on I-66, a motorcycle patrolman who was sitting on the shoulder let me pass, then started after her and pulled her over. I hope he was knowledgeable and gave her a warning and the information she needs about proper licensing. The three times I've been stopped, I've been the one to educate the officer regarding Virginia law.

"When you get to the fork in the road, take it." --Yogi Berra