Complex sentence: The LinuxFund is an organization that raises finances in order to fund Free and Open Source Software (FOSS) projects, with the principal funding source being a LinuxFund Visa affinity credit card from bank US Bank bearing a graphic of Tux, the Linux Penguin.
Split into simpler sentences: The LinuxFund is an organization that raises money and makes donations to Free and Open Source Software (FOSS) projects. To date the principal funding source has been an affinity credit card from bearing a graphic of Tux, the Linux Penguin.