Okay, in the summer I'm off to Greece with some friends, and planned on taking my camera gear with me. There's no way I'm packing my gear into my main luggage, so I'm looking to buy a rucksack that will: 1. Be small enough for hand luggage. 2. Fit two bodies and a few lenses, and a macbook. 3. Be easy enough to open out for security checks. I rarely carry all my gear at once, but I guess I would like to use the backpack for more than just airport travel once I've bought it, so ideally it'll look nice too. Recommendations please!