The Peak Tram takes you up to Victoria Peak, Hong Kong's 1,800-foot-high mountain. Less expensive buses will get you there, too. Once you're up top, admire the views over the city from the hiking trails. The Peak also offers an escape from the subtropical climate below — the air here is cooler and less humid.
Stanley Harbour, on the other side of Hong Kong Island, will give you a taste of a different Hong Kong. It's a fishing village on Repulse Bay with a lovely seaside walk (snap some photos of the fishing boats) as well as a famous street market. There's lots of British history, a boardwalk and even a few beaches. You can take the bus from Central for a scenic trip, though the express bus is faster.