Pack guide books... a bottle of sunblock lotion (if you're visiting in the summer!)... and toiletries. These items are all relatively expensive in Hongkong compared to the U.S.A. and Europe. :-(
However, DON'T PACK camera film... video film... audio tapes... and batteries... because they are ALL bargains in Hongkong!
'Those who visit foreign nations, but associate only with their own country-men, change their climate, but not their customs. They see new meridians, but the same men; and with heads as empty as their pockets, return home with traveled bodies, but untravelled minds.' -Caleb Colton