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4-wheel spinner suitcase - Not only is a suitcase like this foot-friendly, it's also easier to navigate up inclined gangways and down narrow cruise ship hallways.

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Luggage lock - A luggage lock won't stop a determined thief, but it often deters an opportunistic one. Keep your bags secure at all times.

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Cash - Bring enough cash for shore excursions—it beats using a credit card all the time! And in any case, some places don't accept plastic.

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Sunscreen - It's easy to forget how powerful the sun is, especially when being fanned on deck by a cool ocean breeze. But don't be fooled. The Caribbean, Mediterranean, Indian Ocean... these are all very hot destinations. Pack lots of sunscreen.

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Aloe vera gel - Aloe vera gel is widely known to relieve sunburn and help heal wounds. Indeed, aloe vera is touted as the "burn plant," the perfect natural remedy for a bad sunburn. Stock up before leaving home.

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Small cabin fan - Air conditioning is of course standard on all cruise liners. But it's often quite pleasing to have a source of fresh air circulating around the cabin.

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Cabin clock - Your mobile device probably has an alarm as standard, but it's always wise to pack a back-up. After all, you don't want to end up snoozing through those activities on board.

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Sunglasses - Pack a really good pair of sunglasses. Besides sunshine, the glare off the ocean can be blinding. There are two types of sunglasses: UV protection sunglasses protect your eyes from the dangerous rays of the sun; polarized sunglasses eliminate glare. Think of both as sunscreen.

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Outlet adapter - Cabins are notoriously economical with outlet space. Pack a couple of outlet adapters that will expand the number of plugs.

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Towel clips - A breezy deck can prove annoying when you're trying to secure a towel to a lounge chair. Beat the wind with these handy clips.

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Travel day pack - Ports mean shore excursions, and you'll want to travel light while exploring these destinations. A travel day pack is the solution. Ideal for storing snacks, a warm sweater if necessary, and depositing souvenirs.

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Money bag - For convenience, stash some cash in a money bag. Just remember that would-be thieves recognize this accessory for what it is, so wear it under clothing.

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Seasickness relief - Onboard medical facilities on cruise ships operate 24/7, and will have always have seasickness medication on hand for nauseous passengers. But you will still likely want to bring your own.

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Bug repellent - Mosquitoes haven't yet found a way of conquering the world's oceans, but you can be at their mercy in port. Take precautions, especially if cruising the tropics.

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Waterproof drybag - It can happen! A distraction, a slip of the hand, and dunk... your valuables end up soaked. Better to keep them in a splash-proof container so if the worst happens, everything stays dry. Incidentally, drybags are a good idea if you don't want to leave valuables on a beach while swimming.

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Swimsuit cover-up - Modesty is a big issue in some cruise ship destinations. Be prepared to wrap up on dry land when culture dictates. Back on board, it'll make it easier for you to go from swimming to sitting at the bar.

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Cheap waterproof wristwatch - Leave the Rolex in the safe and instead wear a cheap, waterproof option for dips in the pool or a swim in the sea. If it gets lost or stolen, who cares?

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Lanyard - This humble accessory is very useful for putting room cards and sea passes within easy reach, and in plain sight!

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Netflix - In the rare instance when onboard entertainment isn't cutting it, it's useful to have at hand some episodes of your favorite Netflix TV series to pass the time. Remember to download episodes before embarking: accessing the internet on board can be expensive.

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Windbreaker - Don't be fooled by a bright sunny day at sea. A mid-ocean breeze can be surprisingly chilly, more so at night. Pack some warm clothing for when the temperature drops. Of course, if you're cruising the Norwegian fjords in winter, common sense should prevail.

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Binoculars - The world's oceans afford fabulous opportunities for observing wildlife in its natural habitat. Also, if you're cruising along the coast you'll want to spy what's going on ashore. Tip: always use binoculars with a strap around your neck.

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Wide-brimmed hat - Ladies, you can always make a fashion statement under the sun. And it also makes perfect sense to protect your face, shoulders, and neck from getting sunburned.

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Phone dry pouch - Protect mobile devices from water (and harmful salt deposits) by securing them in dry pouches that you secure around your neck.

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Passport dry pouch - Likewise, don't let your passport meet a watery end through carelessness.

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Phone charger - How many of us have left home and are halfway around the world before realizing we've neglected to bring along our cell phone's charger?

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Sticky notes - Handy for leaving quick reminders in the cabin, for letting others know where you are, or for requesting items or services from your cabin steward. It's much cheaper than using the cell or in-house phone.

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Slip-resistant flip-flops - A standard item to pack on any summer vacation, flip-flops for cruising ideally should be those with a textured sole for walking safely around slippery poolside decks.

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Deck shoes - A step further, a pair of comfortable deck shoes is the footwear of choice for cruise-savvy passengers. 

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Beach blanket - Pack some beach blankets made from light, microfiber cloth for lounging around on the sand. Remember, some tourist traps charge an arm and a leg for renting out a simple item like this.

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Ziploc bags - Ziploc bags work wonders for storing documents, travel notes, and paperwork when a larger drybag just wouldn't be practical. Pack a dozen or so for all needs.

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Potpourri - Keep the cabin's WC fresh and sweet-smelling by bringing along your own potpourri. This is also a good idea if the cabin is small, or hasn't got a balcony.

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Portable cabin nightlight - Very useful if you've booked an interior cabin that doesn't have windows.

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Eyeglass repair kit - An eyeglass repair kit is an item easily overlooked, but it's essential if you wear glasses. Alternatively, pack a spare pair of glasses.

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Bottle of wine - Alcohol is an expensive add-on for cruise passengers. Fortunately, many cruise lines allow you to bring on board one bottle of wine or champagne. If you find this is so, take advantage and pack a good bottle.

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Corkscrew -

Oh, and don't forget to pack a corkscrew for your wine. Cheers!

See also: Should you still vacation on cruise ships?

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