Odd text before ":" in Terminal In Terminal.app I have a text prompt like the following

rover-205-89:Documents username$ 


What is the "rover-205-89"? I thought it was my computer name but I looked under System Preferences > Sharing and that isn't it.
That is your computer's hostname. In Terminal type the command hostname and that is what you'll see. You can change the host name with the command sudo scutil --set HostName desired-host-name. There are some networking scenarios where this won't permanently fix the problem, though. (e.g. OS X assumes hostname of other network computer: how to prevent this?). It happens with my machine at work (on a Windows domain). Aside from being a little disconcerting, there are no functional repercussions that I've experienced.