1. A durable, lightweight, smooth rolling wheelie bag that holds a lot and doesnt tip over easily, like the REI Stratocruiser 25, which comes with handy backpack straps and a detachable day pack. Four wheeled bags are even less likely to tip over, but theyre slower to walk with and prone to rolling away when youre standing in line somewhere.
2. A slim digital camera that turns on and focuses quickly; Canons PowerShot series does both jobs well.
3. Duct tape because youll inevitably wish you had some. Packing a whole roll is annoying, so take a 2 ft. strip and wrap it around a pencil or marker.
4. A copy of your passport youll probably never need it, but if you lose your passport, having a copy greatly expedites the process of getting a new one. A scanned copy that you e mail to yourself works fine.
5. One quart Ziploc bags for getting liquids, gels and toiletries through airport security pack a few extra ones in case one rips or someone youre traveling with forgets to bring one.