I did quite a bit of French, German and Latin at school (most of which I've forgotten

) and have dabbled in a little Portuguese and Italian.
I would love to be bi- or even tri- or more lingual, but it's difficult to find the time and opportunites to practice. I think, to really become fluent, you really need to live in a country that speaks the language you want to learn as the main local language. Without that level of immersion (and regular practice thereafter), it seems very difficult to master another language as an adult.
I'd also love to learn Japanese (I watch far too much anime

) but have been rather intimidated by stories from friends who have tried to learn it and given up because it was so difficult!