What should I do in Singapore?

Spotted this on Ask Metafilter. Dude asks what should he do when he is in Singapore. From Ask Mefi:

I want to go to Singapore. I dont know anything about Singapore. I want to experience Singapore. What is there to do? I'm 18 years old.

I'll be leaving late-December, and returning mid-January. Looking for cultural hints (e.g. greet everyone with 'Singapore Hello!') and tips on what to do. I'll be staying with aunt and uncle, but I can roam the city by myself.

He has received some good replies but I like this one the best:

Do not bring, buy, sell, or take illegal drugs while you are there.