Don't know what this is and I've never seen it before but..
I went to upload a file at Filefront and it finished uploading, then gave me the option to register
thing is, the registration fields were already filled in with someone elses (valid) details.
Stupid me didn't think of maknig a note of the name or email address but I remember it having "Skull" in there somewhere.
I mistakingly clicked register with those details and it let me, so couldn't have been a suggested username, password from Filefront themselves.