On the north side of Flower Market is the Mong Kok Stadium, where the best of the best of Hong Kong play footie. Even Nicky Butt (whom Pele once mentioned as his 'player of the World Cup') pulled in the crowds for some games here.
Bring a nice friend and some beers, watch footie, and geocache - what else could a person need? (meditation perhaps, which might help you find this one).
Stealth please. There are many eyes here.