My mother's ex-workcolleague moved to Hong Kong to become a biology teacher (she's extremely qualified, having worked in one of the top girls schools in England alongside my mum)... not sure if she teaches English too. But anyway, in comparison to the UK, professional teaching in Hong Kong is apparently very good - comfortable jobs, reasonable pay, made up for by the lower living costs here too.
So if you're a teacher in the UK, Hong Kong seems like a good choice.
I considered doing some English language teaching, but then realised I'm not *that* qualified, and more importantly, I hate little kids 