I created a scoreboard, but forgot to put a name in. This did work, so now I'm here with a scoreboard without a name. When I use /scoreboard objectives list, this is what I get:

Client> 2013-05-20 10:32:36 [CLIENT] [INFO] [CHAT] §2Showing 1 objective(s) on scoreboard
Client> 2013-05-20 10:32:36 [CLIENT] [INFO] [CHAT] - : displays as '' and is type 'deathCount'

It is, however, impossible to remove the scoreboard, as I can't put a name in. It'll give me this:

Client> 2013-05-20 10:32:58 [CLIENT] [INFO] [CHAT] §cUsage: /scoreboard objectives remove <name>