One of Michael Lopp’s travel tips:
My travel tip is this: every three months, sit down on the floor of your office, take whatever bags accompany you around the planet, open them, and pour the contents on your floor. From there, you are making two piles: shit you need and shit you think you need. My advice: obvious need is easy, and if there is any question in your mind regarding need, put it in the other pile.
I apply this tip to my bag I carry everyday, and do this about every month. I dump it all out and figure out what is unnecessary crap accumulated in my bag from a one time need. I lose a lot of junk every month, junk which would have otherwise kept accumulating. In fact, one thing that is nice about testing new bags is that I clean things up more often.
It takes me about 10 minutes to dump it all out and put it back together, and I’d still do it if it took me thirty minutes.