GnuCash is free (as well as open source). It's cross-platform (Linux, Windows, and OS X) and is one of the most reliable finance applications you will ever use.
Jack Wallen is an award-winning writer for TechRepublic and Linux.com. He’s an avid promoter of open source and the voice of The Android Expert. For more news about Jack Wallen, visit his website jackwallen.com.