@
TravellingBeard
Indeed, I ended up with a very late inbound once and it made no sense to leave airside for the few overnight hours.
Yes, the staff at the front desk have blankets and pillows although not sure how many they keep on hand. There were many people there the night I was, but few were sleeping, most sitting or eating etc.
Also, the SKL in T3 was quite crowded. The showers were always great in my experience.
One of the people who was sleeping in the back near the bar area at the same time I was.
Many of the middle seating areas like this were full of people waiting for their overnight flights.
Also, as for taxis, keep in mind there is a "security surcharge" between midnight and 6 or 7am. Not sure if Grab has the same type of surcharge.
I've paid only about $12 SGD from City Hall station to SIN at 4am, a few dollars more in the morning. All depends on traffic as we know. If flight times allow, I generally prefer to take the subway back to Changi.