Tung Choi Street in Mong Kok runs for several blocks as an open-air market known as the Ladies' Market — the name dates from when it primarily sold women's clothing, though the stalls now cover toys, electronics, phone accessories, luggage, sunglasses, and the usual run of tourist souvenirs alongside the clothes. The market operates from around noon to midnight, with the late afternoon and evening hours being the most crowded.
Prices are negotiable on most items, though with less elasticity than in some other Asian markets. The surrounding streets in Mong Kok are more interesting than the market itself — this is genuinely one of the densest and most lively neighbourhoods in the world, and the market is a good excuse to wander it. The goldfish market on the upper section of Tung Choi Street is particularly worth a detour.