Wine is a free MS-Windows API implementation.

Gigolo is a frontend to easily manage connections to remote filesystems using GIO/GVfs. It allows you to quickly connect/mount a remote filesystem and manage bookmarks of such.

Pithos is a cross-platform desktop client for the personalized web radio Pandora, supporting all important features the official Flash™ client has.

GNU Gnash is a free GPL'd SWF player. It runs as a standalone application on either the desktop or embedded devices, or may be used as a plugin for several popular browsers. It supports playing media from a disk or streaming over a network connection.