If you're going to be in Hong Kong for a few days and planning on travelling around a bit on public transport, you might consider buying an Octopus card.

It's a stored value card, accepted on MTR, KCR trains, Airport Express, buses, ferries...then you never have to worry about fossicking about for correct change, just zap the card on the reader on your way in.

You can buy them at any MTR station, or at the Airport Express Customer Service Centres at the airport station on your way in. There are several different types for sale, some geared to tourists with a certain number of specific journies pre-programmed, some just a standard stored value that works on everything. There is a refundable deposit of HK$50 on the card, and you can also add value to the card at any MTR station, or at many local shops like 7-11 and Park'n'Shop.

If you're going to be hopping on and off trains, buses and ferries, you'll love how easy this little card makes your day...