I think I have decided. I'm going to study Cantonese in Hong Kong besides the computer science stuff. It was not an easy choice to make between studying Cantonese and Mandarin. Mandarin is useful in larger parts of China while Cantonese is the language spoken in an around Hong Kong. But I want to be able to understand what the old lady at the grocery store is saying and besides I think it really helps to hear the language being spoken all around you a lot when you're learning.

But Cantonese use tones even more so than mandarin. I'm a bit afraid of these tones. We're talking about the same kind of tones that you deal with when singing and everyone that has ever played Sing Star knows that hitting the right tone can be far from easy. The tones are used to distinguish one word from another so use the wrong tone and you might be saying a completely different word than you think you are. According to Wikipedia Cantonese "has nine tones in six distinct tone contours" while mandarin has only four. Scary.

These are some of the horror examples I found on this page of what you might say when using the wrong tones:

You try to say: Cigarette lighter (打火機)
But you really say: Beat up the waiter (打火記)

You try to say: Charity (慈善)
But you really say: You're crazy (黐線)

You try to say: My bill, please (埋單)
But you really say: To buy eggs (買蛋)

I bet many Swedes don't know this but Swedish is a tone language too. It's light years away from being as hardcore as Cantonese though. We only have two tones and they are only used in a few words (e.g, anden/anden, tomten/tomten for those who know swedish). I will try to comfort myself with this. Maybe I can learn a tone language - at least I have done it once.