This deal was previously posted by BeeKeeper and expired on 30th September 2009,
However the offer has now been extended with no confirmed expiry date.
I've just spoken to someone at BT and this offer is still running.
This is a great offer if you need a BT socket in your house. The offer applies to new lines, reconnections and second lines. You do have to sign an 18 months contract and the cheapest monthly tarrif is £11.25 if you pay by DD and have paperless billing.
This isn't available online : to get it you need to ring 0800 800 150, lines are open Monday to Friday 8am to 9pm, Saturday 8am to 8pm, Sunday 9am to 6pm. When you call, ask for the 'New line free connection offer'.