Unless you're a psycho bike messenger ninja assassin type, cycling downtown is generally a nightmare. The sidewalks are too clogged with people, not to mention the fact that biking on the sidewalk is against the law in a business district. As for the streets, forget about it. If the SUVs don't get you, the buses will. Even in our most urbane neighborhoods, Houstonians still drive with the rugged individualism lovingly depicted in the documentary film Death Race 2000. All of that is decidedly not so on a Sunday. Especially around dawn and dusk, the streets and sidewalks are blessedly empty, and the city's skyscrapers sparkle in the rising and setting sun like giant pillars of gold. And with the redevelopment down there, you are no longer venturing into a desert — oases are scattered hither and yon to provide liquid refreshment of every type.