A fool and his luggage are soon parted.
A Packing List
maps, guidebooks, phrase books, Post-it® notes, restaurant lists, membership cards, business/calling cards, telephone access numbers
All of these can be important, but also a challenge to your "packing light" goal. Instead of the whole guidebook, perhaps you can cut out — or photocopy — only the section(s) pertinent to your needs, discarding no-longer-required portions as you travel. Or simply summarize the pertinent information in your notebook. For any guidebooks that you do carry, a pad of the smallest Post-it notes will serve as excellent page markers. As travel guides are not always up-to-date (plus, libel concerns prevent them from describing things like tourist traps, and the bad parts of town), check travel Web sites with active user communities (like Thorn Tree and TripAdvisor), which can yield plenty of useful (and current) insider information. Just recognize that some posters have personal agendas.
Guidebooks and the like tend to be quite recognizable as such. You can reduce your "tourist quotient" somewhat by covering them with simple paper covers (as shown at right); these can even be made from old brown paper shopping bags, something you probably learned how to do at school. If you want to try for a really clandestine look, construct the covers from something written in the local language.
Consider replacing a collection of foreign phrasebooks with a Kwikpoint International Travel Translator card (two of its two dozen panels are shown at left), containing hundreds of universally recognized symbols designed to get your message across.
Don't carry maps that can easily be acquired en route. Another good reason to use local maps in place of those you have brought from home is that the former will have place names in the local languages, rather than "translated" into English. This is particularly important if you are touring by car, as you are unlikely to see "Prague", "Florence", or "Munich" on road signs (rather "Praha", "Firenze", & "München").
Laminated maps are particularly desirable: in addition to their increased ability to withstand the rigours of travel, they can be marked up (with the day's destinations/routes/notes/etc.) using a dry-erase pen, and simply wiped clean the following day.
Long distance phone calls can be expensive from foreign countries (for that matter, any phone calls made from a hotel room are likely to be very costly); come prepared with a list of access numbers to reduced cost services (AT&T provides an access list for US calls on their Web site). Even better is the use of international phone cards (with Personal Identification Numbers), widely available at newsstands and the like in industrialized countries.
Business/calling cards are an ideal way to leave your address(es) with newfound friends, and occasionally useful for impressing local officials. Finally, consider carrying a photo or two of your family & home, and/or a few postcards of your city; these help establish your identity as a "real person" to those you meet along the way.
pen(s), small notebook, glue stick
Most journeys will yield interesting items of information along the way (addresses of people you meet, the locations of hotels, restaurants, and other recommended attractions, a record of photographs taken, even a trip diary); make sure you bring along something in which to write them down. There are many possibilities here, ranging from simple to elaborate. Cult-like followings have grown up around such note-taking classics as the French Rhodia pad and the Italian Moleskine notebook, each of which comes in a considerable variety of sizes and paper formats. The ideal solution will also depend on your personal aesthetic and the nature of your journey.
For my part, I prefer to reduce the load on both my feet and bank account via the elegant simplicity of an eight-page, shirt-pocket-sized, "minimalist notebook" (which you can easily make yourself, as shown here); I am rarely without one, whether travelling or otherwise. Its quality is dictated primarily by the nature of the material used to make it — which can range from cheap white copy paper, through quad-lined engineering stock, to elegant, high quality writing papers — and it offers the added benefit of incorporating convenient storage pockets for business cards (your own and others), receipts, and other ephemera. A new one also makes an excellent note-keeping tool for conferences and business meetings: you can keep all your notes for the event in one convenient place, and even scan the whole (unfolded) page later for a permanent, paperless record. I generally make up several at a time, so as to always have a fresh one handy; in an emergency, though, you can turn a used notebook "inside-out" to get eight additional blank pages.
By keeping a record you deepen the travel, you become more aware of what's happening as you record it in the evening or the next morning, whatever it happens to be.
More extended, contemplative travels, however, may be better served by the larger type of hardcover, spiral‑bound journal — such as a 5.5×8.5" (14×21.5cm) artist's sketchbook — into which you can glue the pictures, ticket stubs, business cards, menus, and other memorabilia that will help to recall your adventures in years to come.
(Two pages from my wife's journal — chronicling a portion of a visit to Murano, Italy — illustrate such a diary.)
A glue stick will be particularly useful to those inclined to this journal/scrapbook style of note-keeping: it's non-liquid, non-messy, lightweight, and very convenient to use. Elmer's brand (pictured at right) is the one to beat, based on comparison testing: it goes on purple (but dries clear), washes off easily, is acid free, non-toxic, and photo safe. And it fastens well.
The artistically inclined — those who will actually use a sketchbook for sketching — should know that fastening pairs of pages back to back with a glue stick renders them thick enough for watercolour work.
Packing a spare pen (or refill) is always a good idea: even the best pen can run out of ink at the most inopportune moment. Alternatively, do like the Russian astronauts did, and carry a pencil. Just be sure to carry something, even if you normally disdain to do so: as a minimum, when crossing borders (except at a few very large air- and seaports, where the process may be automated), you'll need to fill out immigration and/or customs forms.
personal address book (stamps?)
Even if you're not planning to write to anyone, it's prudent to have telephone numbers (home numbers, if possible) for your doctor(s) and travel partners (agents, airline/auto/hotel clubs, etc.); they just might help avert a disaster, and even if it's only a flight plan gone awry, you'll get the same service from the folks on the phone as from those at the counters, without waiting in line behind the other 200 passengers.
And don't neglect to include such information in your backup strategy.
If you're a reader, travel prepared; reasonably priced books in your preferred language are not always easy to come by in foreign countries.
Choose paperbacks with dense print, and discard (or trade!) them as you go; many B&Bs and hostels offer small "trading libraries" for this purpose. I've seen particularly zealous minimalists tear out and discard book chapters after they've read them!
When travelling with similarly-inclined companions, choose books of common interest, so you can exchange them among yourselves.
Finally, if your preferred reading material is available in electronic format, and especially if you wish to carry a large number of texts, e-book readers offer an appealing alternative. If you decide on this approach, make certain that your chosen reader will function in the environments in which you like to read (some cannot be read in direct sunlight, for example, so would not work well on a beach). Amazon's superb Kindle Paperwhite (pictured here) has long been the model to beat; it comes in several versions, but the standard one is best for most people.
One way to keep your bag light as you travel (especially on longer trips) is to mail accumulated stuff home; having a few large manila envelopes — or better, those made from (incredibly strong, thin, and light) Tyvek®, as illustrated at right — both aids and encourages this.
When you're travelling on business, carrying several FedEx or DHL forms with your company's preprinted account numbers will facilitate such mailings.
Such envelopes are also useful for saving travel notes, and otherwise organizing your paperwork along the way.