Well, if you are really trying to pinch the pennies (actually, I should say Won), you can start off by scouring the neighborhood for free furniture. Want some extra food or "service" from your local restaurant? Visit them often, be polite, and try to speak Korea (it worked for me!). Want to get free food on your flight home? Terrorize the kids sitting in front of you (works like a charm).
Want free tissues in Korea? Keep an eye out for boxes that local restaurants will drop off at your hagwon. I guess the rationale is that every time you grab a tissue you will scan the menu and the pictures of the food. Sure, tissue is cheap but if you really want to save then you'll have to do what it takes to spare yourself some change. Here are some pictures to show you what I'm talking about:
These were given to me as a "gift" from one of the counselors at my work. I didn't really need them as we had lots of tissue at home. However, I did soon realize that these things end up making great prizes for the kids! The expressions on some of my students when I tried to pull this stunt on them was priceless!