My favourite is easily the Hotel Okura in Tokyo, Japan.
It's a chain now; there are Okuras across Japan and seven others around the world. The hotel in Tokyo is the original. It's peaceful and brilliantly organised and has everything that you'd expect in a good business hotel - good service and modern facilities. There is a great Japanese garden where you can sit while having breakfast, which is a good start to the day, very peaceful. There are lots of restaurants offering different cuisines, although I tend to eat in the restaurants that specialise in Japanese food because I love it; there's a French one that I've visited once in the past few years. The hotel has excellent sports facilities, in particular a good swimming pool. The rooms are perfect business rooms. They're very quiet and everything works! They have a fax machine and computer access.