Travel socks  and travel underwear  are great for people who don't mind doing a little laundry every other night of their trip in exchange for carrying less luggage. They are easy to wash in a sink and dry overnight, so they're ready to go in the morning!

A good pair of zip-off pants  may not be the most stylish item in your wardrobe, but it will be the most versatile! Great for climates prone to quick weather changes and all-day adventures: pants for cool mornings and evenings, shorts for midday!

Shirts  with sleeves that can be rolled up or down are a good bet for quickly changing climates. They're also handy if you plan to be touring in a conservative or religious area: many houses of worship require covered arms.

A lightweight rain jacket --preferably one that can fold into its own carry pouch--is great to toss in a backpack, whether you're just going on a day trip near your house or a three week trek along the Appalachian Trail.

Whether you're headed to Costa Rica, Cairo, or Canada, a hat  is a crucial piece of travel gear. It will keep off the sun in the desert, protect you from rain in the tropics, and conserve body heat in the frozen north. A pair of sunglasses  is a great idea too. 

Sturdy shoes are a must for any vacation. You don't want to miss the sites because you were plagued by blisters! Close-toed shoes provide more support than sandals  and are usually more comfortable, but you need to judge for yourself.

For the ladies: make sure you have a good bra! Poor support can cause back pain and fatigue, especially if you're well endowed. Pick out two or three sturdy bras in neutral colors--white ,nude , and black  are classic.

If you plan on spending a lot of time outdoors in a cold area, silk thermals  are a must! Soft, comfortable and warm, these will keep you cozy for hours out in the snow. Many are even machine-washable.

Luggage is where you stash all your stuff for the trip. Most people need a suitcase  and a carry-on bag  or backpack . Also consider duffel bags , which can store a lot. Don't forget a dopp kit  for storing toiletries.

Inflatable neck rests ,travel pillows , and blankets  can make your trip more comfortable and sanitary. Don't forget a sleep mask  as well to keep out any light.

Motion sickness remedies  are good for people prone to seasickness, while travel air purifiers  can keep you from getting sick! Jet lag remedies  are meant to help you cope with shifting time zones.

Travel alarm clocks  are important--you don't want to miss your flight back home or your shuttle bus to your next destination!

Nothing feels as good as a hot shower after a long day of travel, so don't forget travel-sized cosmetics to make the experience better! Keep them organized in a toiletry bag .

Soap leaves  and hand sanitizing gel  let you wash your hands where running water is hard to find.

A small bottle of multi-purpose soap  can be shampoo, body wash, and even laundry detergent in a pinch.

If you're going to need to do your hair, bring a tiny, foldable travel hair dryer  instead of a full-sized one. If you're traveling overseas, you'll need a voltage converter .

Personal audio and video devices, such as a portable DVD player  or MP3 player , can keep you entertained on even the longest flights.

Stay connected on the road with a netbook  or an iPad . Watch movies, download books, or listen to music all with one device.

Books, magazines, and book lights  give you something to do when you're tired of LCD screens. Thankfully eReaders  won't tire your eyes.

Cameras are better at capturing memories than any souvenir you can buy. If you're looking to create a visual masterpiece, consider bringing along a digital SLR, but a simple point and shoot will suffice.

Combination locks ,passport wallets ,money belts , and ID holders  keep your valuables safe and protected.

Electronic dictionaries and translators and pocket dictionaries  can help you get around most foreign countries.

Travel guides  contain maps, recommendations, and tips on acting like the locals. Whether you're traveling within the U.S.  or throughout Europe , a guide will keep you heading in the right direction.

Maps ,digital compasses , and GPS devices  help you navigate around new places. Purchase a handheld GPS  to help you find your way when on foot.

Travel games  are miniaturized versions of your favorite games from home. Keep the little ones quiet!

Handheld electronic games such as a PSP  or a DSi  don't take up much space, but be sure to pack batteries  or chargers !

Scrapbooks  are souvenirs that you make as you go: paste in ticket stubs, menus, etc.

Music helps everyone chill out after a long day of travel. Travel speakers  and headphone splitters  let you share!

Most MP3 players and eReaders allow you to download audio books onto the device. Give your eyes a little bit of rest.

First Aid kits are an absolute necessity. Don't get caught unprepared in an emergency!

Emergency kits are important for any road trip, and can be used as general tools as well.

Sewing kits  help you mend your clothes so that they will last the whole vacation.

Snack foods keep everyone in a cheerful mood. Chocolates can melt, but nuts, jerky and dried fruit are great for travel. Combine all these delicious elements with a bag of trail mix.