I had created a test repository a time ago with an old version of git-annex. I didn't really used it so I simply deleted the directory by hand. Now I've installed a new version of git-annex  and the old repository stills appears on the webapp, but there is no interface to delete it.

* Old git-annex version: don't remember 
* New git-annex version: I downloaded 3.20130107 (twice to be sure), but for some reason 'git-annex version' reports 3.20130102
* OS: Ubuntu 12.04.1 LTS 3.2.0-35-generic-pae #55-Ubuntu SMP Wed Dec 5 18:04:39 UTC 2012 i686 i686 i386 GNU/Linux