The Singapore Maritime Gallery chronicles the maritime history of Singapore. The exhibits are interesting and informative, and the Gallery is designed for a self-guided tour. It opened in 2012 and is located at the Marina South Pier, perfect for you to pop by just before jetting off (in a speedboat) to Kusu, St John's or the other Southern Islands (speaking of which, I have such fond memories of Clifford Pier!).
By some good fortune, I had a teaser guided tour of the Gallery and the Raffles Lighthouse on Pulau Satumu, The latter is not open to public, unfortunately, so here're some snippets to quell (or pique?) your interest, taken with my mobile (a rarity).
On the ferry. THE View. It takes about 1 hour to get from the Marina South Pier to the island, and you do get really close to the container ships.
The Raffles Lighthouse
Up the Lighthouse
The State Marine Ensign
The State Marine Ensign was created in 1960 and is used on all non-military vessels owned by the government, such as the Coast Guard. According to a construction sheet issued by the Ministry of Defence entitled State Marine Ensign and numbered Misc. 6 of 1960: "The State Marine Ensign shall be a blue ensign with the top left hand quarter of red charged with a crescent sided by five stars in a circle all in white and an eight pointed red and white star in the lower right hand quarter. The ratio of the width to the length of ensign shall be one to two. The colour blue is symbolic of the sea, the crescent and stars are from the State Flag and the eight pointed star represents the mariner's compass." - Wikipedia
Interestingly, apart from the State/Civil Flag of Singapore, there are 4 others - the State Marine Ensign pictured above, the President's Flag, the Red Ensign of Singapore (used for Singapore-registered civilian ships), and the Singapore Naval Force Ensign (used on all vessels owned by the Navy).
The ride back, main island, you've been missed.
More pictures are available on my Flickr (simply click any photo).