I've never used the duct tape, but I just figure it's a lucky charm.
The hardest thing is packing for classes. I'm taking "modular" classes for bioethics master so I fly to Chicago for a week several times a year - need 25 lbs of books this semester. I divide them between 2 suitcases and my monster tote bag.
It's good exercise.
That's the one thing I tend to overpack: books. I'll put several books in my checked luggage, one in my carry-on bag. Then I'll peruse the shops and usually buy more. I'm a hopeless book-a-holic. :)