Seems to only work on some hotels (ones with the "Good Buy" tag). Apparently it has to be a $100+/nt. or more...

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* The promo code (the "Promo Code") for $50 is valid between 12:01 a.m. Central Time on October 1, 2007 and 11:59 p.m. Central Time on October 31, 2007 (the "Promotion Period").
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* The Promo Code is valid only for qualifying purchases made on the Site during the Promotion Period using a valid MasterCard® card. A qualifying purchase means a GoodBuy Hotel which is marked by a "SAVE $50 ICON" , and which is offered by Travelocity during the Promotion Period with a minimum three (3) night stay. Travel dates must be between October 1, 2007 and February 29, 2008.
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* GoodBuy Hotel purchase requires a minimum spend of $100.
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