GO40
SGD$40 off sitewide with minimum spend of SGD$80 or currency equivalent. Valid for new users only.
Found this deal on 'Things to do in Singapore' page. Great value. We've already booked a few activities to explore Sentosa (different accounts) and had no issues. You can also use it to book activities in other countries (tested it for Australia), just need to spend minimum equivalent to SGD$80.
Enjoy :)