Comment Learning Suggestions (Score 1) 1021
Three things that I haven't seen mentioned so far:
1. If you do study abroad, or want to learn a language by immersion, DO NOT GO WITH OTHER ENGLISH SPEAKERS. The temptation to talk with them will be too great. You will end up spending most of your time with them and as a result will learn much less of the target language.
2. A great way to recreationally learn a language is to subscribe to a language learning podcast. Get a kit or a cassette adapter so that you can hook your mp3 player up to your car and listen to it whenever you drive. Whenever you're alone in the car, practice repeating the words aloud. If you don't do this, you'll only learn to understand a language but not how to speak it.
3. If you are ever living are frequently around someone who knows another language, ask them to teach it to you. Most people won't mind, everybody likes showing off personal skills, and this is by far the easiest (not to least expensive) way to learn.
SIDE NOTE: I think it's really hit or miss regarding professional use of a language. A lot of foreigners already know english (i've heard its quick to learn, but difficult to master). But it can never hurt to pick up a new language.