Once considered the sole province of the blue-rinse brigade, cruise ships today are a viable travel option for even the most discerning traveller. Not least among the reasons for this are the onboard casinos. Due to the fact that cruise ships sail in international waters, gambling laws don't apply to these floating palaces and as a result all bets are on.

Just how good are the odds on a cruise ship, though? Cheryl James, a former passenger on the Celebrity cruise liner Infinity lost on their video poker machines before realising just how bad the payback was.

'All the machines have the same payback on Jacks or better: less than 75%,' she recalls.