In a display of what one observer dubbed "fin-de-siecle madness," some financial services companies with Internet intentions enjoyed dizzying stock price run-ups followed by swift selloffs this week.

Analysts attributed the fluctuations to Internet-crazed day traders- individual investors who concentrate on short-term trades.

Limited Time Offer

Save $400 off your subscription. Special offer ends April 30, 2017.

14-Day Free Trial

No credit card required. Complete access to articles, breaking news and industry data.