Or even walking/waiting around with luggage looking like you're just about to head to the airport may solicit other similar cabbie offers of cheap airport trips.

As for the Octopus cards - just order the regular $150 one. Cash it in when you leave if you want, or run the value down and keep it for the next time you're in HKG or pass it to a friend to use.

I have one which I've had for about 7 months and used several times while in HKG. I personally think the tourist pass ones are fairly useless and overpriced.

Note that they will not cover you for the Star Ferry, buses or KCR or other services such as the tram up to the Peak. Some of this will be covered in the HK20 extra value on the card, but you may have to refill it anyway.

You might want to have a look at the MTR Fare table to see what kinds of fares you would be paying on your planned journies:

http://www.mtr.com.hk/jplanner/2005f...le_drl_all.pdf