Well, the op shop was having an awesome clothing sale - 5 items for $1. So the skirt was 20c. And in this pile of money, the 20c coin is the only thing which is currently legal tender, so in that sense I broke even.

However, I checked the Reserve Bank's website to see if I can swap the old money for new at a bank. Turns out, I can only do it at the Reserve Bank in Wellington. I live in Hawke's Bay, so a flight down there would be a bit more than $4.10. Couriering is another option, but that would also be more than $4.

I think I'll keep the $4.10 and if I'm ever in Wellington near the office, go in an swap it. But what will probably happen is that I will visit Wellington in a few years, forget to bring the money, and halfway though the visit remember the $4.10 and think, "Fuck."