GHA (Global Hotel Alliance) has their December flash sale going on for the 2013. You can get up to 40% discount off of the Best Available Rates for stays until March 31, 2014 (dates vary by property).
Note that these rates are prepaid, non-refundable and non-cancelable.
This sale is going on for three days and is likely to end on December 19, 2013. There are no terms and conditions associated with this offer, but you can access GHA’s web page for this offer here.
If you managed to get the GHA Discovery Platinum status during one of the limited time offers, it could be worthwhile to have a look at this sale and the rates that are currently offered by the properties. You may be able to save a bit.