英國有咩出名/獨有的品牌?

boots product, not everything is on sell in HK, and is cheaper here. you can check their website before you shop.
http://www.boots.com/home.jsp
go to the market, there is alot of local produces and home made stuff.
http://www.boroughmarket.org.uk/
http://www.londonmarkets.co.uk/
great make up from the brand lush...
http://www.bnevertoobusytobebeautiful.com/

top shop

Harrods products
Chocolates from famous department stores (e.g. Fortnum & Mason)
Fancy things from Covent Garden

To be honest, most of the products from UK has distributor in Hong Kong.
However, you may be able to pick up some cheaper and good quality products from Outlet or when they are on sales.
I can recommend Radley and Mulberry Bag from UK.