Writing bad checks
Many banks offer overdraft protection that kicks in if you write a check for more than the balance of your account. But writing a check that you know is no good is illegal. The risk isn't negligible: Kaplan says some people do get prosecuted for writing bad checks.
"Not only are there criminal penalties involved, but you get put on a list of bad-check writers," she says. "A lot of places won't accept your checks, and you may have difficulty opening a bank account again because you've been labeled as a fraudster."