If you have a 17" laptop I can really reccomend the Lowepro Compurover AW. Really nice backpack that fits a 17" laptop, crop camera with battery grip, 3-4 lenses and a flash. And that's just in the bottom camera compartment. There is a big compartment in the top of the bag that fits everything else, like cables, memory cards, clothes and other "random" stuff.
I had the Lowepro Computrekker for half a year but never used it because it lacked a compartment for the "random" stuff which the Compurover has
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Oh yeah and comfort with this bag is great. Fully packed with all my camera gear, laptop, tripod and some clothes it is still rather comfy to carry around.
Edit: plus the all-weather(AW) function is a life saver if you live in or travel to a country with shifting weather conditions.