Singapore - Get in

The majority of nationalities can enter Singapore without a visa. Refer to the Immigration and Checkpoints Authority for current guidelines, including a list of the 30+ nationalities that are required to obtain a visa in advance. Entry permit duration (in most cases either 14 or 30 days) depends on nationality and entry point.
Singapore has very strict drug laws, and drug trafficking carries a mandatory death penalty — which is also applied to foreigners. As always, travellers should take care with their baggage and secure it appropriately. The paranoid might also like to note that in Singapore, it is an offense even to have any drug metabolites in your system, even if they were consumed outside Singapore.
Duty free allowances for alcohol are 1L of spirits, 1L of wine and 1L of beer per person. Note that cigarettes cannot be brought in duty free. One opened packet is acceptable, but anything more will be taxed. Foreigners can opt to pay the tax or let the customs officers keep the cigarettes until the next departure; locals get to choose between paying or witnessing the cigarettes being destroyed.

By plane
Singapore is one of southeast Asia's largest aviation hubs, so unless you're coming from Peninsular Malaysia or Batam/Bintan in Indonesia, the easiest way to enter Singapore is by air. In addition to flagship carrier Singapore Airlines and its regional subsidiary SilkAir, Singapore is also home to Tiger Airways, and Jetstar Asia, which recently took over Valuair.

Changi Airport
As befits the country's main airport and major regional hub status, Changi Airport (SIN) is big, nice, and well organized, and immigration and baggage distribution is remarkably fast. There are currently three terminals: Singapore Airlines and most Star Alliance partners operate from Terminal 2 (T2), whereas most other airlines use Terminal 1 (T1). The two are connected by a free "Skytrain" shuttle service, or you can just walk directly across. A new Budget Terminal opened in March 2006 currently handles only Tiger Airways flights and is connected to T2 by free shuttle bus.
If you have over five hours to spare there are free city tours six times a day. Check in at the Singapore Visitor Centre in either terminal. Even if stuck in the airport there are plenty of ways to kill time, including a movie theater (T2) and a swimming pool and jacuzzi (T1). Internet access is provided free of charge, both wirelessly and via some 200 terminals, there are some X-Boxes set up to keep gamers entertained, and there's live lounge music at times. Food options are varied and generally reasonably priced, with some choice picks including the Peranakan-themed Soup Restaurant (T2 landside) and Sakae Sushi (T2 airside). The free fortnightly Changi Express paper "contains news and information on events and happenings around Asia Pacific, in Singapore, and at Changi Airport".
Both terminals T1 and T2 have airside (i.e., accessible without passing through immigration) transit hotels on their third floors - tel. +65-6541-9106 or book online via the Ambassador Transit Hotel website. A six-hour "block" for a single/double/triple costs S$57.75/64.70/86.65, budget singles (shared bathroom) S$40.45, extensions S$13.90 per hour. You can rent a shower (without a room) to freshen up for S$8.40. The Plaza Premier Lounges in both terminals also offer a basic but functional gym with shower for S$8.40 with a Singapore Airlines boarding pass.
From the airport there are a number of ways to get into the city:
Taxi (cab) is easiest - simply follow the signs after clearing customs. Meters are always used in Singapore and prices are reasonable. A trip to the city will be between S$20.00 and S$30.00 (including S$3-5 airport surcharge, but excluding the midnight to 06:00 +50% surcharge if applicable).
Shuttle - six-seater MaxiCab shuttle service to designated areas/hotels costs S$7.00 and can be booked in advance or in the arrivals hall. 06:00 to 02:00, every 15 to 30 minutes.
Subway - MRT trains run from T2, although you must cross the platform to a city-bound train at Tanah Merah. The 30-minute ride to City Hall station costs S$1.40 (plus a refundable $1 deposit for a single-trip ticket). 05:31-23:18 (except Sundays & public holidays - 05:59-23.18) only. Unfortunately for the picky traveller, the stations downtown (e.g., Orchard, City Hall) that are nearest to the more popular and upscale hotels are the last to be upgraded for internal lifts, but if you're travelling by MRT the escalators really oughtn't be a problem.
Bus - bus terminals can be found in the basements of both T1 and T2. 06:00 to midnight only. Fares are sub-S$2.00, exact fare required (no change given).

Seletar Airport
Berjaya Air flights to the Malaysian islands of Redang and Tioman use Seletar (XSP), not Changi (SIN). The only practical means of access to Seletar is taxi; trips from the airport incur a S$3 surcharge.

By bus
Direct to/from Malaysian destinations
Another way in is by road from or via Johor Bahru in Malaysia. There are buses from Kuala Lumpur (KL) and many other destinations in Malaysia through the Woodlands Checkpoint and the Second Link at Tuas. Major operators include:
Aeroline, tel. +603-62588800 (Malaysia). Luxury buses with meal on-board, power sockets, lounge area etc, to KL and Petaling Jaya from S$47 one-way. Departures from Grand Copthorne Waterfront Hotel, Havelock Rd.
NiCE, tel. +65-62565755. Executive express buses to KL. Normal NiCE buses RM60, extra-roomy double-decker NiCE 2 buses S$47. Departures from Copthorne Orchid Hotel, Havelock Rd.
Transnasional, tel. +602-62947034 (Malaysia). Malaysia's largest bus operator, offers direct buses from Singapore through the peninsula. Executive/economy buses RM60/26 to KL. Departures from Lavender St.
Transtar, tel. +65-62999009. Transtar's 16-seater First Class coaches are currently the best around with frills like massaging chairs, onboard attendants and video on demand, but they also cost the most at S$60 one-way to KL. More plebeian SuperVIP/Executive buses are S$25/39, direct service to Malacca and Genting also available. Departures from Golden Mile Complex, Beach Rd (near Bugis MRT).
Other operators include:
Gunung Raya, tel. +65-62947711,
Hasry Express, tel. +65-62949306,
Konsortium Express, tel. +65-63923911,
In general, the more you pay, the faster your trip. More expensive buses leave on time, use the Second Link, and don't stop along the way; while the cheapest buses leave late if at all, use the perpetually jammed Causeway and make more stops. Book early for popular departure times like Friday and Sunday evening, Chinese New Year, etc, and factor in some extra time for congestion at the border.
Another option to taking an "international bus" is to make the short hop to Johor Bahru to catch "domestic" Malaysian long-distance express buses to various Malaysian destinations from the Larkin Bus Terminal. Besides having more options, fares may also be lower because you will be paying in Malaysian ringgit rather that Singapore dollars. The down side is the hassle of getting to Johor Bahru, although this can be done relatively easily. See the following section for connections to Johor Bahru.

By train
The Malaysian state rail operator KTMB [21] runs daily trains, including a sleeper service, from Kuala Lumpur. There is also one sleeper daily along the "Jungle Line" from Kota Bharu in north-eastern Malaysia. The trains are clean and fairly efficient, but slower than buses.
Trains arrive at the railway station in Tanjong Pagar at the southern edge of the CBD, a bit of a hike from Tanjong Pagar MRT station. It's also possible to get off in Woodlands right after immigration.
Note that KTMB tickets in Singapore will be charged in dollars, while those bought in Malaysia will be charged in ringgit at the same rate. A ticket which costs RM10 in Malaysia will thus cost S$10 (RM20!) if bought in Singapore! There are three ways to avoid paying double:
Book your tickets as return tickets from Malaysia. For example, KL-Singapore-KL will be charged at the ringgit rate.
Cross the border by road and then board the train at Johor Bahru. Note that making a reservation is highly advisable; the easiest way is to book online.
Buy the cheapest ticket you can from Singapore to JB, then your 'real' ticket from JB onward. Change to your 'real' seat after crossing the border.
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By boat
Ferries link Singapore with neighbouring Indonesian province of Riau Islands, and the Malaysian state of Johor (regular ferry services to Tioman Island were discontinued late in 2003).
Singapore has four ferry terminals which handle international ferries: HarbourFront (formerly World Trade Centre) near the southern part of the Central Business District, Tanah Merah on the East Coast, Changi Ferry Terminal and Changi Point Ferry Terminal , both at the eastern extremity of the island. Cruise ships use the HarbourFront terminal. HarbourFront and Tanah Merah are managed and operated by the Singapore Cruise Centre [22].
Getting to/away from the ferry terminals:
HarbourFront FT: Located next to HarbourFront MRT station.
Tanah Merah FT: Get off at Bedok MRT station and catch bus No. 35 to ferry terminal.
Changi Point FT: Take bus No. 2, 29 or 59 to Changi Village Bus Terminal and walk to the ferry terminal.

Cruises
Star Cruises [34] offers multi-day cruises from Singapore to points throughout Southeast Asia, departing from HarbourFront FT. Itineraries vary widely and change from year to year, but common destinations include Malacca, Kuala Lumpur, Penang and Malacca in Malaysia, as well as Phuket, Krabi, Ko Samui and Bangkok in Thailand. There are also several cruises every year to Borneo (Malaysia), Sihanoukville (Cambodia), Ho Chi Minh City (Vietnam) and even some ten-night long hauls to Hong Kong. An all-inclusive two-night cruise may cost as little as $400 per person in the cheapest cabin class if you book early, but beware the numerous surcharges and note that non-residents may be charged significantly higher rates.