Some time series data links
climate:
http://www.ncdc.noaa.gov/paleo/data.html
general time series:
www-personal.buseco.monash.edu.au/~hyndman/TSDL/
public health (World Health Organisation data):
www.who.int/research
financial:
finance.yahoo.com
economic: www.bea.gov,
www.federalreserve.gov/releases/
employment (U.S. Department of Labor):
www.bls.gov
demographic:
http://www.mortality.org/
U.S. Federal statistics on almost everything!
www.fedstats.gov/
French epidemiological data (time series for weekly cases by region; click on the UK flag to get the English version)
www.sentiweb.org/