Cut out quote but responding to the above message
If you call up customer care, the representatives can remove you from their mailing list.
This is to also comply with the MPS.
http://www.tpsonline.org.uk/mpsr/
Once registered any company to mail you that doesnt have "To the occupier" can be fined.
Companies are still allowed to mail you under the header "To the occupier" means its not personal, and therefore not harrasment.
NTL merged their customers onto the system that Telewest used.
(Ex employee of Telewest up until Dec 2006.)
The representative can access your account for your address
(Even tho your not a customer, you will have an account for your address)
Then they can access the details for your property and change it to no contact.
However, if your receiving mail from Virgin Mobile as a Virgin Mobile customer I cannot help as im unaware of Virgin Mobiles systems. Plus registering with the MPS only wont cause Virgin Mobile any financial loss if they continue since your an existing customer of theirs, and it only protects you agains unsolicitated mail from companies you are not registered with. (Marketing mail in the same way as cold calling from unknown companies)
Also as Matt D stated 4 for 40 is 1 of many products.
Maybe Internet, and phone is something you would be interested in, give them a ring and see it they can meet or do something that meets your lifestyle