Piles of durian (right) are heaped up in the markets at present - and you can smell them a block away. This fruit seems to inspire a 'love it or hate it' reaction. Some people can't get beyond the pungent, almost rotten odour, while the flavour of the fruit is distinctive - sweet and creamy, with a custard-like texture.
The durian in Hong Kong are from Thailand. When I was in Kuala Lumpur I tasted the smaller Malaysian durian, and liked them even better than the Thai variety; unfortunately, I've never seen them here. In Malaysia, the fruit is so popular that many different types have been developed, and people ask their fruit vendors for the specific variety by name. In Kuala Lumpur I ate durian pancakes, durian cakes, durian pastes, durian tarts - and even went on a search for a mythical durian chocolate (I never found it).
In Hong Kong, most people just eat them raw. A good fruit vendor will help you pick out the ripe fruit. Shake the fruit - if it's ripe the pods inside will be slightly loose, but don't buy if they're too loose, it means the fruit is over-ripe. When you press the spikes on the shell they should bend slightly. If you're buying plastic-wrapped fruit in the supermarket, press it with your fingers - it should 'give' a little. Durian is considered yit hay (heating), so don't eat too much. Mangosteens, which are cooling, are supposed to be a good companion fruit. Drinking water from the durian shell is also said to be an antidote to the fruit's heatiness.