If there was a prize for most surreal cocktail party of the year, it would have to go the World Economic Forum's "Gala Soirée", which was held on Saturday night on the floor of the New York Stock Exchange.
Security was so tight that the whole Wall Street financial district was cordoned off, even to the never-ending stream of ground zero sightseers, and two of Manhattan's busiest highways were closed to traffic while WEF participants were ferried to and from the party by coach, complete with siren wailing police escorts, from the Waldorf-Astoria in midtown.
Ever the showman, Dick Grasso, chairman of the exchange, was there to meet them with a drink and a handshake, as in bemused wonder they wandered around the floor's trading kiosks, with their bizarre mix of old and new technology.
Where normally there is frenzied shouting and trading, there was black tie and evening dress. Latin and African rhythms beat out from the party's four themed bands amid the silence of the trading pits.
One of the last remaining examples of open outcry trading in the world, the New York Stock Exchange shouldn't by rights exist at all in these days of computerised online trading. But it does, a monument to how America treasures and preserves its symbolic institutions when all around is changing.
So is the New York Stock Exchange going to change too? No chance, Mr Grasso said: "We survived 11 September, so we can survive anything."
It was hard to know what Clara Furse, chief executive of the London Stock Exchange, made of it all. The LSE abandoned open outcry many years ago, while Ms Furse was still in her apprenticeship, but as she wandered around the trading pitches, with their touchingly personalised stands, she might have reflected on how much more important the interchange of human contact is over the clinical efficiency of online trading.