I had to extend a recent business trip and came back a few days later than I intended. I sat down to pay bills and it was the day after one of my credit cards had a payment due. I was hit with a $39 late fee, a $9.95 epay fee, and interest retroactively was jacked up to 21%. All together, I was hit with a charge of 1.27% of my balance for being one day late. That works out to an annual yield of 10,000%. Nice for them. Makes one consider supporting regulation.