If people panic on a crowded beach from yelling 'Tsunami', then they're idiots.

If a tsunami is coming, the tide recedes for miles. Any beach-goer who doesn't know this doesn't deserve to be at an oceanic beach.

Probably not a big deal but I figured I better get some one else's opinion first ;-)

Its not that bad I mean if a Tsunami actually was coming I would yell Tsunami becaus it was coming towards the beach.

I think it would get a more interesting reaction if you yell "Avalanche!"

No one will take it seriously, I don't think.

It depends on how you yell it. Right now I'm envisioning a beach so crowded you can barely move, and an hysterical woman pointing to the beach and screaming at the top of her lungs: "Tsuuuuuuuuuunnnnnammmmmmmiiiiiiiiii!!!!" It's really an hilarious thought!