Sorry, I am a day late guys and gals. Sale begins March 23, 2010 at 9am (Pacific Standard Time) and ends March 26, 2010 at 9:00am (Pacific Standard Time).
South Point Hotel, Casino, and Spa in Las Vegas is having a 72 hour sale, offering 50% room rates. Rates from as low as $35.
Reservations must be booked online using promo code EDAY310.
I did a quick search and looks like you can book dates all the way into September!