I had a friend who was an interpreter in Japan (Japanese/English/German) working for multinationals. She made a huge amount of money working for them, so much that after 3 years she returned to the west and bought a house outright (this was about 10 years ago). She was doing a mix of instantaneous translations over phones/in meetings and document translations.

But in saying that she needed about 2 years to recover, it really did "fry her brain" as she told me. And she was highly educated too - a Masters in both languages (native tongue English).

if you want to earn big money go to japan where they pay for want and expect quality. not china where everyone wants cheap and cheerful

I was raised bilingual, Russian and English, I speak both without an accent (I'm also fluent in Ukrainian and Italian) and was an interpreter in the military for twelve years in the Defense Threat Reduction Agency. I have done, and still can do, simultaneous interpretation in both languages, be it Russian-English or English-Russian. I wouldn't recommend working for the EU, and def. don't be a translator - that money is crap. As far as simultaneous interpretation - it is not that hard, but, you have to have a VAST vocabulary (probably at least 10,000 words I'd say), and god forbid your speaker gets technical on you. For example I had a speaker one time go into the aerodynamics of a wing while I was sequentially interpreting (slats, elevon, flaps, etc...предкрылки, закрылки, элерон), luckily I read a lot and I knew it. Anyways, I digress, the point is this, the UN doesn't pay you enough (90K tops) to live in places like New York or maybe even Baghdad, plus for my target language companies like honeywell and gazprom start out at about 120K a year. If I was you though, I'd go another avenue - NSA (you can even buy your military time back and you start out at 80K if you have prior experience) or do something else. Me personally, I started buying up real estate in Kiev, Ukraine when I was 22 and now at 40 I live very comfortably on my military retirement and the dividends I get from renting out my property. Good luck!

Suggestion of working for the US NSA, apparently mostly just because of the pay, involves a certain political question, the answer to which many of us feel should be: "HELL, NO!"