I'm hardly what you'd call a wise old man of the road, but I've picked up a couple of tricks here and there. If you are a seasoned travelling type, these will be obvious, but if you're heading off on your virgin trip they may be some help:
Update 2009: These tips were written in 2000, and the pace of change means inevitably some are a bit out of date. Photography has gone digital - next to nobody travelled with a digital camera in 2000, nowadays film cameras are a rarity, and most Internet cafes are ready to burn memory cards to CD. More and more of the world is connected to electricity, internet and international banking transfer systems. Almost nobody had a mobile phone in 2000 (and those that did, were still a little ashamed about it :-)). This page is left up as a bit of a historical curiosity - you young people today you've got it easy, back when I were a lad etc.
But the bit about earplugs still applies as much as ever. Seriously... :-)
What to Pack.
Earplugs. Trust me, weight for weight, earplugs are simply the best thing you can possibly take traveling - don't leave home without them! Get stuck in a dorm with someone snoring like a bulldozer in the next bunk and you'll thank me... :-)
Sarong. Towel, dressing gown, bedsheet, skirt, curtain, beachmat - a sarong has a hundred uses. Don't even bother with a coventional towel - a sarong is lighter, smaller, dries faster and smells less. When it gets too disgusting, buy a new one.
Rucksack Bag. Just a shabby, shapeless bag you can zip and padlock your rucksack into. Stops the straps getting ripped off by airline baggage handlers, is an extra layer to deter bag slashers and wandering hands, acts as a dirt and dust and rain cover, and generally makes your stuff a little less conspicuous.
Those chainmail things you can get to go over your bag are all very well, but I couldn't be bothered with the weight, and I'm not convinced the slight improvement in security isn't completely outweighed by the fact that it turns your bag into a big advert saying 'HELLO! valuable western traveller stuff in here!'
Clothes. As few as possible... particularly in the tropics, you just don't need that many clothes... Wash more often, ya stinker. On a long trip, clothes will wear out, so you just buy new ones. For cold climates, add a set of thermal undies, a fleece and a 'gore-texy' coat. One (half) decent outfit rolled up at the bottom of the bag can be good for that unexpected one-off invite to a posh restaurant or club. The best principle for packing is always take less *stuff* and have more money available...
Luxury Items. One of my friends always carries a posh dress and a tiny bottle of perfume. If she's having a bad day, she gets dressed right up and puts on a couple of dabs of perfume before dinner. It might be the same old cafe with flies on the light and dogs under the table, but it's enough to give her a lift. Personally, I carry nothing superfluous. Obviously, my diving and camera gear is completely essential. ;-)
You do have to be prepared for the fact that, likely or not, you just might get robbed and loose everything. But you can't eliminate the risk completely even by staying in your little room at home, so you might as well get used to it. Violent crime is still very rare - much more likely is sneak theft, so take as little of value as possible. At the end of the day, posessions - clothes, cameras etc - are replaceable. Yep, it is a pain (and an expense) but you can always just buy new stuff. (Or do without, although admittedly this doesn't apply to clothes.)
Passport and flight tickets are also replaceable, but losing them could be a major pain, and might even involve you having to /shudder/ go home... so keep 'em secure, preferably on your person, whenever feasible. Carry a set of photocopies separately and leave another set at home. Save addresses (email and postal) on the web as soon as you can. The only thing that I would find it heartbreaking to lose would be exposed films.
Every guidebook has a security section full of scary stories and advice, but honestly, it's really not so bad. If you live in the kind of sleepy place where you leave your car keys in the ignition at night, and leave your bag sitting on the side of the road while you go off to have a coffee, then yes, you are going to need to tighten up your act a bit. But the kind of stuff you should do is usually only what, for example, I used to do at home in London as a matter of course - and going over the top and twitching with hyperalertness can be just as bad - a great way of advertising yourself as a possible target as well as alienating friendly people.
It is a cliche but, just about anywhere in the world, the most dangerous thing you are going to do is climb into a car.
Any method of dealing with films is a compromise. My solution is to keep all films in a X-ray film bag (which also helps to keep them cool) get them developed in a reputable lab (slide films developed but NOT mounted) and posted home as soon soon as possible.
Decent print processing is easier to find than slide - one trick is to find a camera shop which doesn't do slide dev and ask them where they would recommend. Dev'n'print labs in third world countries can vary from excellent to appallingly bad. The one time I posted undeveloped films they arrived fine, and this is probably a better solution than trusting to a below-standard lab, but you don't want films (particularly good-quality slide film - print film normally has a longer period before it 'goes off') sitting around undeveloped at home for a long time either.
When buying film, no matter how shiny the premises, always check the expiry date on the box.
I carried: Main camera: Manual SLR (Pentax MZ-M) with 28mm f2.8, 50mm f2 and 80-200mm f4-5.6 lenses, loaded usually with slide film (pref. Fuji Velvia). Snapshot camera: Nikon point'n'snap with 28mm lens, loaded with print film (pref. Kodak Gold).
For a long, non-exclusively diving trip, just (prescription) mask, computer and compass (doubles as dry land compass). You'll get sick of the weight of anything more.
Just about anywhere, you can walk up to an ATM, stick a card in a slot, and walk away with a handful of cash. Most places where you can't do that, you can walk in to the bank with a Visa card and get cash over the counter. A handful of US dollars hidden about your person can still be valuable for emergencies, and travellers cheques still have a use as a backup, though they can be more of a hassle than they are worth. (I once spent two hours in a Turkish bank trying to cash a couple of cheques, when there was a shiny Visa ATM right there winking at me and saying "I bet you wish you had a PIN number', eh!")
For a long trip, it is useful to have someone at home with the authority to manage your account - even if it is just getting a balance, though internet banking is going to make that unneccessary pretty soon.
It is still possible to get to places with no internet access, but if a place has reasonably stable electricity and a phone line, you can bet there'll be a couple of internet cafes competing for your custom. Ironically, it can be harder to get access in more affluent nations, where if someone wants to get on the web they buy a computer. Elsewhere in the world, they go down the internet cafe, so don't be surprised to find them full of locals.
In general, you want to nail down the specifics of your route as little as possible - the more specific your itinerary is, the more you WILL want to change it. Of course it is good to have a rough list of highlights that you don't want to miss, and it is very worthwhile to research the different seasons of your route. For example, being caught in the middle of a rainy season can get really depressing, quite apart from the practical difficulties of services closing down, roads getting washed away etc.
Guidebooks are all very well, but even the best are far from impartial and up to date. Talking to people on the road is the best way of getting genuine up-to-date recommendations of places to stay, things to see, companies to use/avoid, and the more footloose you are, the more you'll be able to take advantage of these.