This news just in from the Nats. Here's straight from their press release...

The Washington Nationals today announced they will offer individual game parking passes to fans for all 2008 home games at Nationals Park. The opportunity to purchase individual game parking is only available online by visiting nationals.com/waytogo. Individual game parking is available in the following locations:

Green Lot HH $15 per game
Orange Lot W $20 per game
Red Zone $40 per game

"After careful review of the experience of the first weekend, the team is pleased to make available yet another amenity for fans, daily parking spaces at various price levels," commented Stan Kasten, President of the Washington Nationals.

To take advantage of this opportunity, fans must pre-purchase the parking passes at the team website, nationals.com/waytogo. Passes cannot be purchased on-site at specific garages or lots.