The next big tsunami may happen in the Atlantic Ocean.

Studies by the Benfield Hazard Research Center have indicated that the Cumbre Vieja Volcano in the island of La Palma, in the Canary Islands has not erupted for more than three decades. If this happens, the wave hitting North America would be up to 50 meters high and surge up to 20km inland. Morocco could get up to 100 meter high waves. Brazil would see 40 meter waves. Here is an ILM Rendition of the catastrophe. Although insurance lossesare estimated to be in the multi-trillions, the site has been completely unmonitored since 1997. The BBC has a brief article, and a FAQ on the Mega-tsunami. Also Gwynne Dyer has an article on it from August 2004. And here is the Slashdot discussion.