Laptop ergonomics are terrible to begin with. When combined with hotel rooms (where chairs and desks are the wrong height) you’re going to get wrist, shoulder, and back problems before you know it. A laptop stand such as the Roost (or it’s much cheaper clone the Nexstand) raises the laptop to the correct height, resulting in a much better posture. They fold away to a small size and weigh very little. Since I got my Nexstand I’ve noticed big improvements in my shoulders and neck.
Noise cancelling headphones
If you’re doing a lot of flying or bus trips, these will change your experience in a big way. Noise cancelling works best for repetitive droning noises such as engines. Unfortunately they come at a high price, so if you’re on a budget then some good earbuds that sit firmly in your ears will do. This sort of thing is available in malls all over SEA, but I have yet to find any that don't break within a couple of weeks. I'm convinced that defective merchandise gets rerouted to countries with weak consumer protection laws.
A decent camera
You’re going to be having the time of your life, so you might be a bit disappointed later if all you have to capture it is a mid range phone. Having something with a bit of zoom makes a drastic improvement to photography.
There is a noticeable difference in image quality with DSLR cameras (the ones with interchangeable lenses). When I was getting into photography I got the cheapest DSLR I could find, the Canon 1100D and it has served me very well. It's been dropped, banged into stuff and exposed to all kinds of dirt and dust (without a case) and it keeps on going. However it is a bit bulky, so I'd go for a Sony A6000 if I had to replace it today. The A6000 has a standard micro usb port on it so you can charge it anywhere. Check out these photos taken by the A6000!
There are no enforced noise regulations so karaoke, roosters, motorbikes and construction noises are difficult to avoid. Air-conditioning units and fans are often not maintained so their noise can disrupt sleep, making ear plugs a lifesaver for light sleepers. However finding a shop that sells them can be difficult because local people are accustomed to the noise and don't care about it. Hardware stores are your best bet if you run out of your home supply.
The movies on TV and in the cinema (if there is one!) will often be in a foreign language or not to your taste so you’ll frequently be watching movies and TV on your laptop. The sound quality is not the best on laptops and even a small portable speaker will improve your at-home movie experience. My X-Mini kai speaker was one of the best pre-travel purchases I've made.
Band aids, oral rehydration salts, and diastop (pretty self-explanatory: for travel on days when your bowels don’t want you to). These can all be bought locally, but if you need them you probably won’t be in a mood to buy some so stock up before anything bad strikes.
All the local TV is just about unwatchable so you'll probably be looking to stream video content quite frequently (just google <movie name> putlocker" and try a few different search results - almost any movie that's come out on DVD or Netflix will be there). It's nice to watch those on a bigger screen with better speakers, so having a HDMI cable to hook up to the TV will make your movie/TV night a lot more enjoyable. Mac users will need a DisplayPort to HDMI converter in addition to the cable. The one I linked to has DVI/VGA output also, making it ideal for using hired monitors in coworking spaces.