Cruise ship life can be a little mysterious. Your choices aren't always spelled out in black and white. The more you cruise, the more you pick up on the unofficial secrets the cruise lines don't tell you -- which give you more options, let you save money and generally allow you to have a better time onboard.

Maybe it's knowing what your cabin steward is able to bring you or what the off-the-menu items are at the bar or dining room. Or perhaps it's a tip to getting a good deal on an onboard purchase.

But why wait to figure these things out the hard way -- possibly after you've missed your chance? We trawled through all the great advice on Cruise Critic's Message Boards to bring you some of the worst-kept cruise secrets ... at least among our readers who love to share. But whether you're a first-time cruiser or an old sea dog, you might find there's something here you didn't already know.