http://us.megabus.com/Megabus%20Offers%20200000%20Free%20Seats.aspx -make a trip with dates between January 9 and February 28 and enter promo code: TRYMEGABUS to make it free. It seems to mostly only work on Midweek trips. They have 200,000 free tickets available but it’s spread through all of their routes. I believe most trips have a $.50 surcharge