Here’s a great coupon which you need to keep around, since it’s valid all the way through April 30, 2014! (However, if a lot of people use it, it will not longer be valid. It’s only good for 15,000 uses.)
Coupon code: MASTERCARD (but you don’t need to use Mastercard to pay)
10% off a hotel-only booking for any price match guarantee hotel, which is almost every hotel on Hotels.com.
Note that this coupon is only valid on the Hong Kong web site. You can change the location on the top of the homepage, and select whichever currency you want. Prices are the same across all Hotels.com web sites.