I leave for a two year trip of Australia, Indonesia and S.E Asia on sunday.
My carry on luggage consists of -
Nikon D300 + MB-D10 grip
Nikon 17-55 2.8
Nikon 70-200 2.8 vr
Nikon 105 2.8 vr micro
Nikon 1.7 TC
Nikon SB900 speedlight
6x EN-EL3e battery's
2x sets of AA Sanyo eneloop's (for the flash)
5x 8GB Sandisk Extream CF cards
Olympus TG-1 (for underwater and times when an SLR is not a good idea)
Better Beamer
Set of soft grads, three stop solid grad and a polarizer
Hyperdrive Colourspace UDMA 2 750GB (invaluable for backing up pics)
Lens cloths and pens
Lenscoat rain sleeve
Lowepro Flipside 400AW (carries all of the above)
Laptop
In the hold luggage is -
Various chargers
Masterplug 4-gang, 2 USB surge protected extension lead
Think Tank Hydrophobia 70-200 Flash (for rainforest treks)
Induro monopod with Custom Brackets tilt head
Full sensor cleaning kit
It sounds like a lot but when its packed away it really doesnt look much, and if your going to be heading into remote areas its better to have everything you need with you.
My main subject matter will be wildlife with some landscape and portrait thrown in as well.
Hope my silly list helps to give you some ideas and hope you have a great trip