it's not a station, it's like a... mini-station. You anchor it (the control tower) at a moon and a spherical forcefield goes up, you can't get inside the forcefield without access (can be configured to allow corp members, alliance members etc, and/or a password can be set). You can anchor modules inside the forcefield like hangars, assembly arrays, laboratories and such. You can anchor guns outside of the forcefield to defend it, as well as ewar modules. You can do lots of things with em. They're particularly useful in wormhole space where there are no stations. They're the only way to live there semi-permanently.
You people should come wormholing with me :{)