Hong Kong is a great place for buying cameras... Just remember to do the following:
* Stick to authorized dealers... Never buy a gray market camera no matter how cheap.. You may get problems with warranties in the future.
* Research on current prices and make the seller aware that you know how much a certain camera goes for. Do some haggling, haggling and even more haggling...That's the only way you get a better deal.
* Know the whole package... Some cameras come with free accessories. Some sellers (Mongkok is notorious for this) sell the cam at a cheap price but will omit the freebies that are really included in the package... ie, lens cap, cam strap, charger, cam bag, free lens etc... and will try to dupe you by saying you have to buy each item individually.
Overall, HK has more cam choices, and more cam stores than any place in Asia. And if you're an informed buyer, HK is the best place to buy stuff...
As for the other items.... Well HK is also a good place to buy "white books" -- which are actually generic design/assemble-your-own laptops. Haven't bought one yet, but I saw this at windsor tower near causeway bay... its really neat when you can actually do the laptop specs yourself... at half or 1/3 the price of branded laptops.
* bought two cameras in HK, one from Mongkok, one from Causeway