Having spent just a few days in Singapore as a stop over, I'd like to highly recommend one activity: Jacuzzi, sauna and swim at the airport.
It's well known that Singapore's airport is one of the best in the world, and for around £10-15, you can have the ultimate luxury.
Check-in first, and go straight through to departures. You can then enter the health club and lie back in an outdoor Jacuzzi and watch planes over your head, just an hour before boarding your plane. I've never felt so refreshed for a flight!
Singapore Airport, after Check-In
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