The house advantage in double-zero Roulette is 5.4%. Most shipboard casinos these days have good Blackjack rules that bring the house edge down to about 0.5% with basic strategy. Another possibility is betting the Don't Pass with full odds on craps.
When casinos have this type of chip there is often a way to change them into slot tokens as well.
I'll be on the Voyager of the Seas on the 18th for the World Poker Tour so I'll report back what I find.
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