As the exchange rate as of 29th of May at 23.15 CET (Paris Time) is 1 US dollar=0.813471081 euros you would need € 122.02 for a BlizzCon ticket, as I assume one of the few reasons one would like to...
Exchange rates change frequently as the value of each country's currency rises or falls based on economic and other conditions. Today, June 6, 2009, the value of 100 Euros is $141.80 US.