I either take my Thinkpad X60s or my macbook on every job. Weight matters.. If you need a lot of mobility the toughbook T series can go a long way in the travel world (they are not resistant to being stepped on however). There is nothing worse than lugging around a huge laptop, pulling it in and out of your bag at security.
Also check out flyclear.com for fast track at security lines..
airplane power adapters are crucial on the overseas flights.
For phone, nokia n95 or iphone, either one will give you data over wifi when you are in a bind, and both can give you mapping from your location (preference on the n95 overseas). Stick with GSM as it works anywhere.. AT&T had an unlimited blackberry international data plan once upon a time, but I am not sure if that is still the case.... it saved me thousands of dollars several times.
a good bluetooth headset is also good to keep on hand for skype/SIP calls back home, or long conference calls.
if you frequently have to check your luggage, and have excessive gear, look into getting a durable pelican case for everything.. make sure the case will fit in an overhead bin however..
I am sure this goes without saying, but bring plenty of pens and paper, and keep them in your pocket for when gadgets are too cumbersome.
as always, stick to the essentials, and do your best to never check luggage.. sooner or later you will end up at home with what you need. If you want more media, get a bigger HD, don't lug around unnecessary peripherals.
When traveling for pleasure I leave all the gear behind to disconnect, thats what vacation is for.
best of luck...