According to a german TV show (BizzTV), most of the (letterbox) companies that are registered under the following address:
6 9 G r e a t H a m p t o n S t r e e t
B 1 8 6 E W B i r m i n g h a m
U n i t e d K i n g d o m
are very dubious companies. Before you sign up, register, or do anything on a site which has that contact address, think twice and read carefully the Terms of Service etc. and remember that e.g. no one is giving you something (e.g. DVD’s) for free just for regsitering on a website, even if it is written on the website. Be careful.