Forget about being the “Big O”… Opera is making waves in the Atlantic. Literally.

If you aren’t familiar with Opera, it’s an alternative web browser that’s been around longer than Firefox. It’s quite fast, although the only free version does feature advertising. (Still not obtrusive, though.)

Opera recently released Version 8.0 for download, and with the sudden burst of recent activity for Mozilla’s Firefox browser, Opera CEO Jon von Tetzchner made a bold (cold) promise: If Opera-8 gets 1-million downloads in the first four days of release, he’d swim from Norway to the United States.

Oops. Now, he’s all wet. As in already in the water on the way to America.

“Although I blatantly admit that my promise was based more on joy and enthusiasm than my swimming abilities and physical health, I will do my very best to keep it,” he said in a statement.

He’s not totally insane, though. First of all, he’s taking his PR guy with him. Spokesman Eskil Sivertsen is rowing a boat alongside (presumably as punishment for releasing the braggadocious statement to begin with.) Sivertsen is bringing along a satellite phone, maps, food, water and a book with inspirational quotes from the Viking sagas.

“It’s the least he can do, having put me in this situation in the first place,” says Jon S. von Tetzchner with a wicked grin on his face. “Besides, I can’t swim to the USA without maps, and this wet suit doesn’t seem to have any pockets, so it’s good to have him there – also as someone to talk to along the way.”

The photo ops alone make this a winner. Opera gets tons of free publicity, the image of a corporate leader who stands by his word, and the “ocean voyage to America” theme harkens back to conquest — which is a good place to position your third-place browser with less than 1-percent market share.

(PS: If you want to try Opera, don’t worry about the “AdWare” designation. It loads the ads as you surf, and the ads stay in the same banner near the browser buttons. It doesn’t load additional sneaky software onto your machine.)

Update: “Brave CEO saves PR Manager in Dramatic Rescue at Sea.” Just brilliant.