At a previous job (over a decade ago), I worked on software that stored prices in centipennies. I'm pretty sure it's no longer in production. At least, I hope it isn't.

But these things sometimes surprise me. A few years ago I paid a visit to my coworkers at the job I had in high school in the mid nineties. I had written some sort of email processing program in C; I don't even remember what it did any more. I was told they are still using it, 25 years later. Awesome or scary, I don't know which.