I live in one country and work in another, flying some 100+ times a year. I love the TT Urban Disguise 60 and have used it now for over 2 years of travel. Holds my laptop, camera, lenses, a flash or two, all my spare HD's and bits, etc as well as a book, food and other stuff. Best of all it looks like a simple light laptop bag and has never once been questioned. I often carry 10-12 kilo in it and although recently the strap broke, TT fedex'd me a new one overnight to Jerusalem once I had emailed them a photo of the broken part. Lifetime warranty and they are good for it. If you don't carry all your gear with you every time you fly, if you're a PJ, etc, it's a very very good bag for flying with. Can't recommend it enough.
Something to keep in mind is that when flying from the UK they will weigh your hand luggage often. If it's a cheap airline then it's a given. Something like a TT Airport Antidote and certainly a pelican may well be over the weight limit when empty! When flying with a certain airline they would weigh the hand luggage again just before boarding to include all your duty free purchases (nasty people!). The people at the desks are usually mindless morons (in the UK at least and I'm English, I can say it ) a trick is to go to check in without your hand luggage, get a friend to hold it somewhere unseen, check in holding a book or something in your hand to look realistic then pick up your bag quietly afterwards and go to security. Another favorite trick if they will weigh your bag is cameras over your shoulder under your coat, load your pockets with lenses and hard drives, heck even ask your friend just to hold your laptop while you check in!
I personally have switched to a netbook rather than my powerful 3kg toshiba monster with 2 extra batteries. With my Asus 1000HE netbook, 320GB HD and 2GB RAM I get 8+ hour battery life (and I have two), it's slow but powerful enough to edit entire weddings, that's 1300+ RAW files in LR from RAW to completed jpg ready for the lab. It also does all my music, films, ebooks, yada, yada in a package a fraction of the size and weight of my previous laptop. Yes it's slow but I forgive it everything for it's tiny size. When you fly that much believe me it makes a huge difference. I couldn't even fully open my Toshiba in cattle class...
As for the battery chargers, tough one. I keep chargers for both cameras and laptop in both countries to be honest, I can't afford to arrive without when I'm shooting a wedding the next day. A camera battery charger is not big, put it in your coat with the plug and cable in your checked luggage, any electronics store will sell the canon cable at least, not sure about other manufacturers.
If your country has retina scan or fingerprint scan machines at customs, sign up for it! Nothing is more fustrating after the hell that is modern flight than having to wait in a long queue because a flight just got in before you with 200 half drunk toughs back from Majorca I'm signed up in both countries and boy does it make my life easier.
I hate flying so very much but hey, got to live...