The New York Times in its Sunday edition carried an excellent article on the impact of Japan's earthquake on global supply chains. Japan is a leading producer of Silicon wafers used in the microchips. With the production of such wafers halted after the earthquake, the IT sector will feel the impact when the existing inventories exhaust in the next few months.
Also, worth noting is the anecdote about a call to a senior HP executive at 3:30 AM about the earthquake and the follow-up meetings of the senior HP execs to plan for the eventualities within hours of the earthquake.
Quake in Japan Broke a Link in Global Supply Chain - NYTimes.com