The code can be purchased from the ISSAbove.com web site as a downloadable SD card image that you write to your own SD or MicroSD card.
Setup is accomplished using a simple browser based admin system where the user selects their location from a google map interface. The Raspberry Pi's Timezone is then set as appropriate.
The system utilizes the ISSAbove.com web site in order to send tweets "to" the International Space Station whenever it makes a particularly close pass above the users location. Check out the @ISSAboveYou twitter feed for the more than 45K tweets already sent by ISS-Above devices around the world.
The newest version of ISS-Above connects to an HDMI monitor. Extensive information about the ISS and upcoming pass data is displayed to the TV.
Whenever the ISS is in sunlight the system automatically streams live video views of the earth from the space station as provided by NASA.