Speakup allows you to interact with applications and the GNU/Linux operating system with audible feedback from the console using a synthetic speech device.
Speakup is licensed under the GPL; the GNU General Public License.
Speakup allows you to navigate around the screen using the typical screen review functions such as say word, say line, announce cursor position, which console your currently on, and much, much more. It also allows one to load in configuration parameters for controlling various aspects of the synthesizer you are using, as well as speakup itself. You can review the current default key assignments here.