"As J.P. Morgan pointed out in a report at the end of last week, US information technology shares are now worth $2,700bn (£1,626bn) - slightly more than the value of all shares in the UK equity market, the world's third largest. Microsoft alone is worth as much as all listed Italian companies together."
Back in 1989, Nippon Telephone & Telegraph was capitalized at more than the entire German stock market. Not, of course, to suggest that past performance is any guide to future results.
Doug