What's the soundtrack to the most crowded, wealthiest and most seismically unstable capital city on the planet? After 36 years of experimenting with thousands of songs, Tokyo cab driver Toshiyuki Anzai believes he knows: Frank Sinatra, Wagner and Deep Purple. Throw in a little Abba, Louis Armstrong and Natalie Cole to liven up the mix and steer clear of anything Japanese. Take along a bottle of bubbly, just in case. The mood-setter, though, is Bobby McFerrin's 1988 iconic megahit Don't Worry, Be Happy. 'See, guys get into the cab without telling their girlfriends what's happening, so the girls sit there in the back seat looking all nervous and unhappy,' says the 67-year-old music lover. 'I stick on that song, and they begin to relax a little. Then we're off.' In a city teeming with more than 50,000 taxi drivers, most of whom seem to grumble about the perilous state of their trade, Anzai sells a popular and unique service. For 12,000 yen (HK$970), he ferries customers at night around Tokyo's streets on an 80-minute tour of its greatest landmarks, signposted with his own handpicked mood music. Despite the hefty price tag and the souring economy, Anzai says he has never been busier. 'People come to my website because they've read or heard about me' he says over the sound of Enya's plaintiff Celtic warbling. 'They know they're going to get something special.' As the car cruises in a loop from Tokyo Station around the bay area and back into the city centre via Tokyo Tower, he explains every twist of the road, and the music that accompanies it. The soundtrack is altered to suit the mood of the people in the back seat, who include retirees, businessmen and lovers of all ages. 'Ok, so we're approaching what I call 'Little New York',' he shouts over the sound of Sinatra. 'This is where I bring people who want to get married. It looks like Manhattan, no? Very romantic.' Since inaugurating Jazz Taxi in 2000, Anzai says he has taken hundreds of couples to this spot, overlooking the northern tip of Tsukishima Island, an area of extravagantly priced apartments and high-rises on the Sumida River that sprung up in the 1990s. From the vantage point he chooses, it looks a little like the lower end of Manhattan viewed across the river from Brooklyn. 'They go down to the riverfront and if the woman says 'yes', the guy gives me a signal. By the time they come back to the car, I have the champagne opened. I might even play them something on my harmonica. In more than 30 couples, I've never had anyone say no to a proposal,' he says. Once, he was asked to take a terminally ill cancer patient on a tour to the site. 'His son called and said he wanted to cheer him up. When he got into the car he was as grey and spindly as death. But when he saw this place, his eyes shone. Three weeks later, he was dead.' Anzai has loved American culture and jazz - the art form it gave to the world - since his teens, but he has never been to New York or the US. 'To be honest, I don't like travelling and I hate getting on planes,' he says. Instead, he watches TV and looks at maps. 'I have a big world map on my desk at home and I pore over it all the time.' For years, he listened to music in his car between breaks until one day a customer liked what he heard and asked him to turn it up. Jazz Taxi was born when he realised that he could put his job and passion together. 'I figure the two things in this world that I really know are music and Tokyo. And I thought that jazz and this city go so well together,' he says. 'Both are improvised and complicated.' Anzai speaks little English but knows how to explain the lyrics of most of the songs he plays, thanks to years of dedicated work with a dictionary and, recently, the internet. 'The Net is a godsend,' he shouts from the driver's seat. 'All the lyrics are translated online for free.' Japan's rich library of music doesn't get a look-in on his i-Pod because he says, 'it doesn't work' for him. 'The rhythms are wrong for cruising or something.' His cab is equipped with a state-of-the-art sound system: a library of 11,000 tunes hooked up to a Japanese power amplifier and a set of antique Russian-made vacuum tubes in the trunk. The car is a Korean-made Hyundai, which has a thicker body than Japanese vehicles, meaning 'a richer, cleaner sound'. He cranks up a demonstration while easing onto the city's elevated expressway and Deep Purple's Highway Star roars from the speakers. 'It's now very jazzy but it works well for this section of the road, right?' Steppenwolf's Born to be Wild kicks off as the speeding jukebox glides past the downtown district heading for the reclaimed waterfront of Odaiba. Anzai was born in wartime and say he is astounded every day by the resurrection of his beloved home. Tokyo was carbonised under a barrage of US bombs in 1945 and lives in constant fear of another earthquake, like the one that levelled the city in 1923. 'Everything you see here was just wasteland or sea until the 1950s,' he recalls. Today, the city and the area that surrounds it is the most crowded metropolis on earth, home to 35 million people, with an economy larger than India's. Many believe it has passed its peak; that it has started to decline as all great cities inevitably do. But for now, Anzai tells his passengers that the best place to see it is from Rainbow Bridge, the flood-lit architectural wonder that spans the north of Tokyo Bay. Built at the tail end of the bubble economy, a now infamous era of hubris and financial folly that crashed in the 1990s, the bridge offers a 360-degree view of the city spread out in all its twinkling nighttime glory. Suitably, for such an overwhelming sight, the soundtrack is Wagner's Ride of the Valkyries. 'I've had punters cry at that scene,' he says. The jazz cruise ends across the bay at the foot of Tokyo Tower, taller than the Eiffel Tower on which it was modelled in the late 1950s. Anzai takes his fares here for a photo before dropping them off back at Tokyo Station. Some day soon, he knows he'll be too old for these tours, which he says he loves doing: he gets to sleep late, work in the evening and clock off in the wee hours. 'It's the best time to see the city because it lights up and it becomes really spectacular. I'm biased, but I think it's the most beautiful place in the world.' Jazz Taxi's website can be found at http://homepage2.nifty.com/jazztaxi/ . Bookings: (81) 90-35-270-312 (Japanese only)