Hi!
I moved back to Singapore after being away for 2 years. I too was a bit "worried" about having to take a test to get the driver's licence. But, luckily, I had saved our old ones which had been valid until Nov 98. So, I thought I'd give it a go and went to the Traffic Police HQ at Ubi Avenue 3 about a month ago around 4 pm and came out 10 minutes later with driver's licences for me & my husband. It was possible, because our licences were not over 3 years old. At least that was what the kind lady there told me. One year licence costs S$20, a 3 year one S$60. She did ask for my passport and green card (dependant's pass), my husband was abroad at the time, but I got his licence without his passport.
So, I was very happy. Finally something that worked like clockwork.