Washington Photo Safari (washingtonphotosafari.com) is offering a 10% discount to customers of Tripper Bus, a bus line that runs nonstop between NYC and DC. Just use the code TRIPPERBUS when you are booking your tour. And check out Tripper Bus for a comfortable ride from NYC to DC and back again, complete with electrical outlets and wifi. You can't beat the price: less than a large tank of gas, and you don't have to worry about parking a car! MUCH cheaper than a train.