Travel light and you can sing in the robber's face.
Packing List > Specialty Items
Items on this page definitely fall into the "optional" category, the need for them being very much a function of personal interests and the nature of the trip. This part of the list could, of course, be arbitrarily long; I have restricted it to a few topics that are of extremely broad interest.
camera (lenses? flash? tripod? film? extra batteries? charger? download adapter?)
I'd recommend a state-of-the-art "point and shoot" camera, unless you really want to lug that SLR around. Philip Greenspun offers an extended and helpful discussion of this topic.
The digital camera user is spared the difficulty of coping with film, but must instead deal with batteries. Choosing a camera that uses a standard battery (especially the ubiquitous AA size) will help considerably, as will the use of high-efficiency batteries and chargers (unlike those that are typically bundled with the original camera). Thomas Distributing is a good source of such technology. Consider also the use of higher-capacity memory cards; one can capture hundreds of high-resolution photos on a 256MB (or higher) card, greatly reducing (even eliminating) the need for downloading during your trip. If you're carrying a laptop, of course, you can download photos to the computer as you go; be sure to bring the necessary adapter to make the connection.
cellular telephone (charger?)
Travel is often best accomplished in the absence of "instant telephony", but for many, cell phones are a business trip necessity. Before you depart, ensure that the phone's technology, your calling plan, and the battery charger are all compatible with the area(s) you intend to visit.
Remember that many phones include tools (alarm clock, calculator, address book, even a sort of "emergency flashlight" in the form of a bright display screen) that you might otherwise have to carry separately. Most cell phones these days incorporate a camera as well, and while their quality is insufficient for decent prints, they make handy "visual notebooks", able to quickly record things you might otherwise forget: the location of your parked car, your hotel room number, the sign on that tourist attraction you visited, and such. SMS messages to oneself can be used for similar purposes (making note of flight schedules, pick-up times, etc.); Google Mobile provides a very full-featured SMS-based service for finding out everything from sports scores and maps to stock quotes and the closest pizza places.
laptop computer (flash drive? power cord/adapters? network cable(s)?)
Even the smallest and lightest laptop occupies a great deal of space, and contributes a significant amount of weight. For business trips they may be a requirement, but for leisure travel can often be replaced by a judicious use of Internet cafés.
You can greatly augment the use of borrowed computers by carrying a flash drive (a tiny storage device that connects to a USB port, and looks to the computer like a disk drive; these go by several other colloquial names, such as "key drive" and "thumb drive"). Such a device makes it easy to bring along personal files, and even useful applications
(make sure the latter will run directly from the drive, and not require installation on the host computer). A flash drive is also excellent for backing up files (including copies of important documents, though I don't recommend this as the primary means of such backup — flash drives can be lost/stolen/damaged just as easily as the original documents), and transferring them between computers. Be careful: some of these devices have built-in "features" that automatically load software onto the host computer. The best price point at the moment is a 2GB flash drive; I like the Kingston DataTraveler II (pictured at right). You can find slightly cheaper makes, but you'll likely sacrifice quality and/or data transfer rate.
If you must bring the laptop, of course, don't forget its attendant extras: power supply (with cord and any necessary adapters), network cable(s), and any needed accessories.
(solar) calculator
Depending on how arithmetic-challenged you are, one of these might help you with currency conversion. Some are available with quite impressive foreign language dictionaries built in. Get a solar-powered design to reduce the need for batteries.
gifts
A final suggestion is to think about taking along some small items that you can present to people you encounter along the way, especially the children (there is no faster way to endear yourself to the families you meet). The colourful (economical, flat) press-on stickers you can generally buy near gift wrapping supplies are appropriate for many ages. Another good idea is to carry a supply of the balloons used to make animals, hats, and the like. You've almost certainly seen this done, and perhaps never realized how easy a skill it is to learn (at least for simple items). T. Myers Magic will provide the instruction — including how to blow up the balloons without popping your eyeballs — and the supplies.
For adults in less industrialized areas, inexpensive (but not cheap, throwaway) ballpoint pens are a good choice; they also make good bargaining chips at markets. High quality fish hooks will be very scarce in poor fishing communities, making them excellent gifts and trade goods (especially for fish!); make sure you get the flat variety. Bandannas, not widely available outside North America, are another good choice. Other adults may appreciate a souvenir (perhaps a small flag pin) of your home country; as a Canadian, I often carry some of our $1 gold-coloured "loonie" coins (so named for the loon pictured on its reverse side).
In anything at all, perfection is finally attained not when there is no longer anything to add, but when there is no longer anything to take away.
