Teach Overseas?

On Monster I often get a job listing for teaching English abroad. I finally took a look at one of the sites cited. What always strikes me are the perks offered: 20 hours of teaching each week, overtime pay, fully furnished and paid for apartment, health benefits. This would be great if it allowed me to put $20,000 in the bank and learn another language (or brush up on the other one aside from English I know and currently teach). Unfortunately, I think the conversion amounts to under $10,000 for most of the listings which are typically in Korea or China or other Asian places. Have any of you done this or doing this now?