Currently, Ebay is offering $50 Hotels.com gift cards for $40! Hotels.com has the best inventory of any OTA that I’ve seen, so this basically nets to an extra 20% discount on any hotel that you want, in addition to portal cashback and any other promotions Hotels.com may be offering at the time you book. You can find the deal here:
Note that there have been a few purchasers who have indicated that they got charged for a cash advance when making the purchase, but if you can avoid using Paypal, you should be okay (Doctor of Credit has a writeup of the last time this happened with a merchant). Reviews of the merchant are fine otherwise.
Even better, Hotels.com gives you the option to combine gift cards, allowing you to use more than 1 if you can get your hands on them (the deal itself is limit 1, but you can expect that these will hit gift card resellers soon or you can ask your friends to buy them for you). Find the combine link here: