There are several agencies in the United States government that are independent and not part of a federal cabinet department. Some examples of independent agencies include:
Central Intelligence Agency (CIA)
Environmental Protection Agency (EPA)
Federal Communications Commission (FCC)
Federal Reserve System (FRS)
Federal Trade Commission (FTC)
National Aeronautics and Space Administration (NASA)
Securities and Exchange Commission (SEC)
Note that the specific agencies that are considered independent may vary depending on the classification and organization of the government.