It is probably not a hot news for some but I only learned about it a couple of days ago. Previously if you would sign up for voipcheap.co.uk, voipstunt.co.uk, voipbuster, etc you would get free geographical phone number. Not anymore unfortunately :(
So, for those of you who definitely want second line with additional phone number, take a look at https://secure.sipgate.co.uk/
Sipgate offering. Their prices are not so good compared to Betamax companies, but they giving you free phone number.
If your VoIP device (like mine) can be configured for use with several VoIP accounts, then you can configure Voipcheap as a primary account for outgoing calls and Sipgate for incoming. I've tried it and it works :)
Oh, and that was my post #1000! :D