I don't know about you, but I find false friends entertaining. Anytime someone gets two similar sounding words that have completely different definitions mixed up, it can lead to some pretty funny moments.
The most enjoyable for me is when English speakers misuse embarazada when trying to speak Spanish, mistaking it to mean embarrassed. Too often I've heard:
"Ay, lo siento. Estoy embarazada."
It's even funnier if a man says it, since embarazada actually means pregnant =)
What are some of your favorite false friends (between any languages)?
Well, in Brazilian portuguese we have a lot of false friends. For example:
Apologize: in portuguese 'apologize' seems a word 'apologia'. 'Apologia' meaning defend something.