As I work for the Intercontinental group, we get special friends & family rates for hotels under the group (Intercontiental, Holiday Inn, Crown Plaza, etc). It's usually a good 15-25% cheaper than the cheapest available rate.
Since got this lobang so thought I share:
Instructions quite straight forward and listed on the above link. Just put my name (Timothy Tan) and hotel (Intercontinental Singapore) on the voucher.