I've been travelling (when not working) for about 7 years now and three things are major game changers for me:
Replacing paper books with a Kindle. I read .. a lot .. and find it's a great way to pass the time in airports, on long bus rides, etc. A lot of my travels are in Asia where the availability of English books isn't the greatest so I would pack several books in my back. Shit's heavy! Then, I got my Kindle! I just load it up before I go and never worry about the extra weight!
Google Maps - With the knowledge that I can find my way "home" if I get lost I am much more at ease with exploring. In Taipei I randomly got off at train stations. Confidently walked down any street I found interesting. I rode motorcycles (well .. scooters) throughout the Thai countryside. Every time I got "lost" I easily found my way back.
Airport Lounges - Layovers ... we all hate them. Sitting in uncomfortable chairs. Overpaying for a beer. Screaming kids. When I got my American Express card it came with access to airport lounges. This is such a game changer! Now I relax in a quiet area with strong wifi, free booze, showers, etc. I really don't know how I travelled before this.